Zadanie 1: Napisz równanie prostej przechodzącej przez dwa punkty: a)A=(8,3) B=(0,4) b)A=(5,−2) B=(5,3) c)A=(2,−3) B=(5,−3) Rozwiązania: a)A=(8,3) B=(0,4) y=ax + b 3=8a+b 4=b 3=8a + 4 −8a=4−3 −8a=1 / : (−8) a= −1/8 b = 4 y= −1/8 + 4 b)A=(5,−2) B=(5,3) y=ax+b −2 = 5a+b / *(−1) 3=5a + b 2= −5a – b 3= 5a + b 5=0 równanie sprzeczne, brak prostej c)A=(2,−3) B=(5,−3) y= ax+b −3 = 2a + b / *(−1) −3 = 5a + b 3= −2a – b −3= 5a + b 3a=0 / :3 a=0 −3=2+b −3+2=b b=−1 a=0 y= x−1 Zadanie 2: Znajdź współczynniki kierunkowe prostych: a) −3x + y – 2 = 0 b )x + 3y − 1 = 0 c) −4x + 3y + 5 = 0 d) 1/2x + 1/5y = 1 Rozwiązania a) −3x + y – 2 = 0 y= 3x+2 współczynnik kierunkowy = 3 b )x + 3y − 1 = 0 3y= −x+1 / :3 y= −1/3x+1/3 współczynnik kierunkowy = −1/3 c) −4x + 3y + 5 = 0 3y= 4x−5 / :3 y= 4/3x – 5/3 współczynnik kierunkowy = 4/3 d) 1/2x + 1/5y = 1 1/5y= −1/2x+1 / *5 y= −5/2x+5 współczynnik kierunkowy = −5/2 Zadanie 3: Napisz równanie prostej równoległej do prostej l, przechodzącej przez punkt P, jeśli a)l: 2x – 7y + 4 = 0 P=(−1,−5) b)l: y = −5x + 2 P=(2,−3) c)l: y = 1/2x – 2 P=(4,0) d)l: −2x + 7y + 1 = 0 P=(3,3) Rozwiązania a)l: 2x – 7y + 4 = 0 P=(−1,−5) −7y = −2x−4 / : (−7) y=2/7x + 4/7 a= 2/7 f(x)=ax+b f(−1)=2/7*(−1)+b f(−1)= −2/7+b −2/7+b= −5 b= −5+2/7 b= −4 i 5/7 (minus cztery i pięć siódmych) a=2/7 y=2/7x – 4 i 5/7 b)l: y = −5x + 2 P=(2,−3) a= −5 f(x)=ax+b f(2)=−10+b −10+b= −3 b= −3+10 b=7 a=−5 y= −5x+7 c)l: y = 1/2x – 2 P=(4,0) a=1/2 f(4)=1/2*4+b f(4)=2+b 2+b=0 b=−2 a=1/2 y=1/2 – 2 d)l: −2x + 7y + 1 = 0 P=(3,3) 7y=2x−1 / :7 y=2/7x – 1/7 a=2/7 f(3)=2/7*3+b f(3)=6/7+b 6/7+b = 3 b=3 – 6/7 b=2 i 1/7 a=2/7 y= 2/7x + 2 i 1/7 Zadanie 4: Napisz równanie prostej prostopadłej do prostej l, przechodzącej przez punkt P, jeśli a)l: 2x – 3 P=(4,−1) b)l: x – 3y + 4 = 0 P=(1,1) c)l: y = 2/5x – 1 P=(10,3) d)l: 2x + 7y – 1 = 0 P=(2,−2) Rozwiązania a)l: 2x – 3 P=(4,−1) a= −1/2 f(4)=−1/2*4+b f(4)=−2+b −2+b = −1 b= −1+2 b=1 a= −1/2 y= −1/2x + 1 b)l: x – 3y + 4 = 0 P=(1,1) −3y= −x−4 / : (−3) y= 1/3x + 4/3 a= −3 f(1)= −3+b −3+b=1 b=4 a= −3 y= −3x+4 c)l: y = 2/5x – 1 P=(10,3) a= −5/2 f(10)= −5/2*10+b f(10)= −25+b −25+b = 3 b= 3+25 b=28 a= −5/2 y= −5/2x + 28 d)l: 2x + 7y – 1 = 0 P=(2,−2) 7y= −2x + 1 / :7 y= −2/7x + 1/7 a= 7/2 f(2)= 7/2*2+b f(2)=7+b 7+b = −2 b= −9 a= 7/2 y= 7/2x – 9 Zadanie 5: Oblicz obwód trójkąta o wierzchołku: a)A=(−2,0), B=(−1,2), C=(2,−4) b)A=(2,2), B=(4,−1), C=(6,2) c)A=(−3,2), B=(−1,4), C=(2,0) Rozwiązania a)A=(−2,0), B=(−1,2), C=(2,−4) |AB|=√(Xb−Xa)2+(Yb−Ya)2 |AB|=√(−1+2)2+(2−0)2 |AB|=√1+4 |AB|=√5 |AC|=√(Xc−Xa)2+(Yc−Ya)2 |AC|=√(2+2)2+(−4−0)2 |AC|=√16+16 |AC|=√32 |BC|=√(Xc−Xb)2+(Yc−Yb)2 |BC|=√(2+1)2+(−4+2)2 |BC|=√9+4 |BC|=√13 Obw |ABC|=√5+√32+{13} Obw |ABC|=√50 (Dobre są te wzory dla tego zadania?) b)A=(2,2), B=(4,−1), C=(6,2) |AB|=√(4−2)2+(−1+2)2 |AB|=√4+1 |AB|=√5 |AC|=√(6−2)2+(2−2)2 |AC|=√16 |AC|=4 |BC|=√(6−4)2+(2+1)2 |BC|=√4+9 |BC|=√13 Obw |ABC|= √5+√13+4 Obw |ABC|= 4 √18 c)A=(−3,2), B=(−1,4), C=(2,0) |AB|=√(−1+3)2+(4−2)2 |AB|=√4+4 |AB|=√8 |AC|=√(2+3)2+(0−2)2 |AC|=√25+4 |AC|=√29 |BC|=√(2+1)2+(0−4)2 |BC|=√9+16 |BC|=√25 |BC|=√5 Zadanie 6: Znajdź równanie symetralnej odcinka AB a)A=(5,−1), B=(−3,3) b)A=(3,−2), B=(−1,6) Rozwiązania a)A=(5,−1), B=(−3,3) y=ax+b −1=5a+b 3=−3a+b / *(−1) −1=5a+b −3=3a−b −4=8a / :8 a= −1/2 −3=3*(−1/2)−b −3= −3/2−b −3+3/2= −b −1 i 1/2 = −b /*(−1) b= 1 i 1/2 S=(x,y) x=1 ; y=1 S=(1,1) a=−1/2 czyli 2 y=ax + b b= −1 y=2x – 1 b)A=(3,−2), B=(−1,6) y=ax + b −2 = 3a + b 6= −1a + b /*(−1) −2= 3a + b −6 = 1a – b −8 = 4a / : 4 a= −2 czyli 1/2 S=(x,y) x=1 ; y=2 S=(1,2) 2= 1/2*1+b 2=1/2+b 2 – 1/2 = b b=1 i 1/2 y=1/2x + 1 i 1/2 Zadanie 7: Podaj środek i promień okręgu o równaniu a) (x−5)2 + (y−3)2 = 36 b) x2 + (y+7)2 = 3/4 c) x2 + y2 – 4x = 21 d) x2 + y2 + 6x – 10y + 30 = 0 Rozwiązania a) (x−5)2 + (y−3)2 = 36 S=(5,3) r=6 b) x2 + (y+7)2 = 3/4 S=(0, −7) r=√3/2 (pierwiastek trzy przed dwa) c) x2 + y2 – 4x = 21 S=(4,0) r=√21 d) x2 + y2 + 6x – 10y + 30 = 0 x2+y2−2ax−2by+c = 0 −2a=6 / : (−2) a= −3 r2=√a2+b2−c r2=√36−30 r2=√6 r=6 −2b= −10 / : (−2) b=5 c=30 S=(−3,5) r=6
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Solution for 10x^2-31xy+15y^2=0 equation: Simplifying 10x 2 + -31xy + 15y 2 = 0 Reorder the terms: -31xy + 10x 2 + 15y 2 = 0 Solving -31xy + 10x 2 + 15y 2= 0 Solving for variable 'x'. Factor a trinomial. (2x + -5y)(5x + -3y) = 0 Subproblem 1 Set the factor '(2x + -5y)' equal to zero and attempt to solve: Simplifying 2x + -5y = 0 Solving 2x + -5y = 0 Move all terms containing x to the left, all other terms to the right. Add '5y' to each side of the equation. 2x + -5y + 5y = 0 + 5y Combine like terms: -5y + 5y = 0 2x + 0 = 0 + 5y 2x = 0 + 5y Remove the zero: 2x = 5y Divide each side by '2'. x = 2.5y Simplifying x = 2.5y Subproblem 2 Set the factor '(5x + -3y)' equal to zero and attempt to solve: Simplifying 5x + -3y = 0 Solving 5x + -3y = 0 Move all terms containing x to the left, all other terms to the right. Add '3y' to each side of the equation. 5x + -3y + 3y = 0 + 3y Combine like terms: -3y + 3y = 0 5x + 0 = 0 + 3y 5x = 0 + 3y Remove the zero: 5x = 3y Divide each side by '5'. x = 0.6y Simplifying x = 0.6y Solution x = {2.5y, 0.6y} Solution for 10x^2-31xy+15y^2=0 equation: Simplifying 10x 2 + -31xy + 15y 2 = 0 Reorder the terms: -31xy + 10x 2 + 15y 2 = 0 Solving -31xy + 10x 2 + 15y 2= 0 Solving for variable 'x'. Factor a trinomial. (2x + -5y)(5x + -3y) = 0 Subproblem 1 Set the factor '(2x + -5y)' equal to zero and attempt to solve: Simplifying 2x + -5y = 0 Solving 2x + -5y = 0 Move all terms containing x to the left, all other terms to the right. Add '5y' to each side of the equation. 2x + -5y + 5y = 0 + 5y Combine like terms: -5y + 5y = 0 2x + 0 = 0 + 5y 2x = 0 + 5y Remove the zero: 2x = 5y Divide each side by '2'. x = 2.5y Simplifying x = 2.5y Subproblem 2 Set the factor '(5x + -3y)' equal to zero and attempt to solve: Simplifying 5x + -3y = 0 Solving 5x + -3y = 0 Move all terms containing x to the left, all other terms to the right. Add '3y' to each side of the equation. 5x + -3y + 3y = 0 + 3y Combine like terms: -3y + 3y = 0 5x + 0 = 0 + 3y 5x = 0 + 3y Remove the zero: 5x = 3y Divide each side by '5'. x = 0.6y Simplifying x = 0.6y Solution x = {2.5y, 0.6y}
Zadanie 1: Napisz równanie prostej przechodzącej przez dwa punkty: a)A=(8,3) B=(0,4) b)A=(5,−2) B=(5,3) c)A=(2,−3) B=(5,−3) Rozwiązania: a)A=(8,3) B=(0,4) y=ax + b 3=8a+b 4=b 3=8a + 4 −8a=4−3 −8a=1 / : (−8) a= −1/8 b = 4 y= −1/8 + 4 b)A=(5,−2) B=(5,3) y=ax+b −2 = 5a+b / *(−1) 3=5a + b 2= −5a – b 3= 5a + b 5=0 równanie sprzeczne, brak prostej c)A=(2,−3) B=(5,−3) y= ax+b −3 = 2a + b / *(−1) −3 = 5a + b 3= −2a – b −3= 5a + b 3a=0 / :3 a=0 −3=2+b −3+2=b b=−1 a=0 y= x−1 Zadanie 2: Znajdź współczynniki kierunkowe prostych: a) −3x + y – 2 = 0 b )x + 3y − 1 = 0 c) −4x + 3y + 5 = 0 d) 1/2x + 1/5y = 1 Rozwiązania a) −3x + y – 2 = 0 y= 3x+2 współczynnik kierunkowy = 3 b )x + 3y − 1 = 0 3y= −x+1 / :3 y= −1/3x+1/3 współczynnik kierunkowy = −1/3 c) −4x + 3y + 5 = 0 3y= 4x−5 / :3 y= 4/3x – 5/3 współczynnik kierunkowy = 4/3 d) 1/2x + 1/5y = 1 1/5y= −1/2x+1 / *5 y= −5/2x+5 współczynnik kierunkowy = −5/2 Zadanie 3: Napisz równanie prostej równoległej do prostej l, przechodzącej przez punkt P, jeśli a)l: 2x – 7y + 4 = 0 P=(−1,−5) b)l: y = −5x + 2 P=(2,−3) c)l: y = 1/2x – 2 P=(4,0) d)l: −2x + 7y + 1 = 0 P=(3,3) Rozwiązania a)l: 2x – 7y + 4 = 0 P=(−1,−5) −7y = −2x−4 / : (−7) y=2/7x + 4/7 a= 2/7 f(x)=ax+b f(−1)=2/7*(−1)+b f(−1)= −2/7+b −2/7+b= −5 b= −5+2/7 b= −4 i 5/7 (minus cztery i pięć siódmych) a=2/7 y=2/7x – 4 i 5/7 b)l: y = −5x + 2 P=(2,−3) a= −5 f(x)=ax+b f(2)=−10+b −10+b= −3 b= −3+10 b=7 a=−5 y= −5x+7 c)l: y = 1/2x – 2 P=(4,0) a=1/2 f(4)=1/2*4+b f(4)=2+b 2+b=0 b=−2 a=1/2 y=1/2 – 2 d)l: −2x + 7y + 1 = 0 P=(3,3) 7y=2x−1 / :7 y=2/7x – 1/7 a=2/7 f(3)=2/7*3+b f(3)=6/7+b 6/7+b = 3 b=3 – 6/7 b=2 i 1/7 a=2/7 y= 2/7x + 2 i 1/7 Zadanie 4: Napisz równanie prostej prostopadłej do prostej l, przechodzącej przez punkt P, jeśli a)l: 2x – 3 P=(4,−1) b)l: x – 3y + 4 = 0 P=(1,1) c)l: y = 2/5x – 1 P=(10,3) d)l: 2x + 7y – 1 = 0 P=(2,−2) Rozwiązania a)l: 2x – 3 P=(4,−1) a= −1/2 f(4)=−1/2*4+b f(4)=−2+b −2+b = −1 b= −1+2 b=1 a= −1/2 y= −1/2x + 1 b)l: x – 3y + 4 = 0 P=(1,1) −3y= −x−4 / : (−3) y= 1/3x + 4/3 a= −3 f(1)= −3+b −3+b=1 b=4 a= −3 y= −3x+4 c)l: y = 2/5x – 1 P=(10,3) a= −5/2 f(10)= −5/2*10+b f(10)= −25+b −25+b = 3 b= 3+25 b=28 a= −5/2 y= −5/2x + 28 d)l: 2x + 7y – 1 = 0 P=(2,−2) 7y= −2x + 1 / :7 y= −2/7x + 1/7 a= 7/2 f(2)= 7/2*2+b f(2)=7+b 7+b = −2 b= −9 a= 7/2 y= 7/2x – 9 Zadanie 5: Oblicz obwód trójkąta o wierzchołku: a)A=(−2,0), B=(−1,2), C=(2,−4) b)A=(2,2), B=(4,−1), C=(6,2) c)A=(−3,2), B=(−1,4), C=(2,0) Rozwiązania a)A=(−2,0), B=(−1,2), C=(2,−4) |AB|=√(Xb−Xa)2+(Yb−Ya)2 |AB|=√(−1+2)2+(2−0)2 |AB|=√1+4 |AB|=√5 |AC|=√(Xc−Xa)2+(Yc−Ya)2 |AC|=√(2+2)2+(−4−0)2 |AC|=√16+16 |AC|=√32 |BC|=√(Xc−Xb)2+(Yc−Yb)2 |BC|=√(2+1)2+(−4+2)2 |BC|=√9+4 |BC|=√13 Obw |ABC|=√5+√32+{13} Obw |ABC|=√50 (Dobre są te wzory dla tego zadania?) b)A=(2,2), B=(4,−1), C=(6,2) |AB|=√(4−2)2+(−1+2)2 |AB|=√4+1 |AB|=√5 |AC|=√(6−2)2+(2−2)2 |AC|=√16 |AC|=4 |BC|=√(6−4)2+(2+1)2 |BC|=√4+9 |BC|=√13 Obw |ABC|= √5+√13+4 Obw |ABC|= 4 √18 c)A=(−3,2), B=(−1,4), C=(2,0) |AB|=√(−1+3)2+(4−2)2 |AB|=√4+4 |AB|=√8 |AC|=√(2+3)2+(0−2)2 |AC|=√25+4 |AC|=√29 |BC|=√(2+1)2+(0−4)2 |BC|=√9+16 |BC|=√25 |BC|=√5 Zadanie 6: Znajdź równanie symetralnej odcinka AB a)A=(5,−1), B=(−3,3) b)A=(3,−2), B=(−1,6) Rozwiązania a)A=(5,−1), B=(−3,3) y=ax+b −1=5a+b 3=−3a+b / *(−1) −1=5a+b −3=3a−b −4=8a / :8 a= −1/2 −3=3*(−1/2)−b −3= −3/2−b −3+3/2= −b −1 i 1/2 = −b /*(−1) b= 1 i 1/2 S=(x,y) x=1 ; y=1 S=(1,1) a=−1/2 czyli 2 y=ax + b b= −1 y=2x – 1 b)A=(3,−2), B=(−1,6) y=ax + b −2 = 3a + b 6= −1a + b /*(−1) −2= 3a + b −6 = 1a – b −8 = 4a / : 4 a= −2 czyli 1/2 S=(x,y) x=1 ; y=2 S=(1,2) 2= 1/2*1+b 2=1/2+b 2 – 1/2 = b b=1 i 1/2 y=1/2x + 1 i 1/2 Zadanie 7: Podaj środek i promień okręgu o równaniu a) (x−5)2 + (y−3)2 = 36 b) x2 + (y+7)2 = 3/4 c) x2 + y2 – 4x = 21 d) x2 + y2 + 6x – 10y + 30 = 0 Rozwiązania a) (x−5)2 + (y−3)2 = 36 S=(5,3) r=6 b) x2 + (y+7)2 = 3/4 S=(0, −7) r=√3/2 (pierwiastek trzy przed dwa) c) x2 + y2 – 4x = 21 S=(4,0) r=√21 d) x2 + y2 + 6x – 10y + 30 = 0 x2+y2−2ax−2by+c = 0 −2a=6 / : (−2) a= −3 r2=√a2+b2−c r2=√36−30 r2=√6 r=6 −2b= −10 / : (−2) b=5 c=30 S=(−3,5) r=6
Solution for 10x^2-31xy+15y^2=0 equation:2
Simplifying 10x 2 + -31xy + 15y 2 = 0 Reorder the terms: -31xy + 10x 2 + 15y 2 = 0 Solving -31xy + 10x 2 + 15y 2= 0 Solving for variable 'x'. Factor a trinomial. (2x + -5y)(5x + -3y) = 0 Subproblem 1 Set the factor '(2x + -5y)' equal to zero and attempt to solve: Simplifying 2x + -5y = 0 Solving 2x + -5y = 0 Move all terms containing x to the left, all other terms to the right. Add '5y' to each side of the equation. 2x + -5y + 5y = 0 + 5y Combine like terms: -5y + 5y = 0 2x + 0 = 0 + 5y 2x = 0 + 5y Remove the zero: 2x = 5y Divide each side by '2'. x = 2.5y Simplifying x = 2.5y Subproblem 2 Set the factor '(5x + -3y)' equal to zero and attempt to solve: Simplifying 5x + -3y = 0 Solving 5x + -3y = 0 Move all terms containing x to the left, all other terms to the right. Add '3y' to each side of the equation. 5x + -3y + 3y = 0 + 3y Combine like terms: -3y + 3y = 0 5x + 0 = 0 + 3y 5x = 0 + 3y Remove the zero: 5x = 3y Divide each side by '5'. x = 0.6y Simplifying x = 0.6y Solution x = {2.5y, 0.6y} Solution for 10x^2-31xy+15y^2=0 equation:
Simplifying 10x 2 + -31xy + 15y 2 = 0 Reorder the terms: -31xy + 10x 2 + 15y 2 = 0 Solving -31xy + 10x 2 + 15y 2= 0 Solving for variable 'x'. Factor a trinomial. (2x + -5y)(5x + -3y) = 0 Subproblem 1 Set the factor '(2x + -5y)' equal to zero and attempt to solve: Simplifying 2x + -5y = 0 Solving 2x + -5y = 0 Move all terms containing x to the left, all other terms to the right. Add '5y' to each side of the equation. 2x + -5y + 5y = 0 + 5y Combine like terms: -5y + 5y = 0 2x + 0 = 0 + 5y 2x = 0 + 5y Remove the zero: 2x = 5y Divide each side by '2'. x = 2.5y Simplifying x = 2.5y Subproblem 2 Set the factor '(5x + -3y)' equal to zero and attempt to solve: Simplifying 5x + -3y = 0 Solving 5x + -3y = 0 Move all terms containing x to the left, all other terms to the right. Add '3y' to each side of the equation. 5x + -3y + 3y = 0 + 3y Combine like terms: -3y + 3y = 0 5x + 0 = 0 + 3y 5x = 0 + 3y Remove the zero: 5x = 3y Divide each side by '5'. x = 0.6y Simplifying x = 0.6y Solution x = {2.5y, 0.6y}
a) y=3x-2
b.) y=-2/3x+2/1/5