Rozwiaz uklady rownan A) 2(x-1)+(y+2)=4 3(x+1-(y-3)=7 B) 3(x+2)+2(y-2)=1 (x+2)-4(y-1)=1 C) -2(x-3)-.... Question from @Kaassiiaaa

December 2018 1 11 Report

Rozwiaz uklady rownan
A)
2(x-1)+(y+2)=4
3(x+1-(y-3)=7
B)
3(x+2)+2(y-2)=1
(x+2)-4(y-1)=1
C)
-2(x-3)-(4-y)=0
5(x+1)+3(2-y)=17
D)
4(x+3)-2(y+1)=0
2(y-1)-(3-x)=-10

Pliss pomozecie?

lewander0 A.
$\left \{ {{2(x-1)+(y+2)=4} \atop {3(x+1)-(y-3)=7}} \right. \\ \left \{ {{2x-2+y+2=4} \atop {3x+3-y+3=7}} \right. \\ \left \{ {{2x+y=4~~~~--> y=4-2x} \atop {3x-y=7-6}} \right. \\ 3x-(4-2x)=1\\ 3x-4+2x=1\\ 5x=5~~~~/ :5 \\ x=1\\y=4-2 \cdot 1=4-2=2$
B.
$\left \{ {{3(x+2)+2(y-2)=1} \atop {(x+2)-4(y-1)=1}} \right. \\ \left \{ {{3x+6+2y-4=1} \atop {x+2-4y+4=1}} \right. \\ \left \{ {{3x+2y=1-2} \atop {x-4y=1-6}} \right. \\ \left \{ {{3x+2y=-1} \atop {x-4y=-5~~~~-->x=4y-5}} \right. \\ 3(4y-5)+2y=-1\\12y-15+2y=-1\\ 14y=14~~~~/:14\\y=1\\x=4 \cdot 1-5=4-5=-1$
C.
$\left \{ {{-2(x-3)-(4-y)=0} \atop {5(x+1)+3(2-y)=17}} \right. \\ \left \{ {{-2x+6-4+y=0} \atop {5x+5+6-3y=17}} \right. \\ \left \{ {{-2x+y=-2} \atop {5x-3y=17-11}} \right. \\ \left \{ {{-2x+y=-2~~~~-->y=2x-2} \atop {5x-3y=6}} \right. \\ 5x-3(2x-2)=6\\ 5x-6x+6=6 \\ -x=0\\ x=0\\ y=2 \cdot 0-2=-2$
D.
$\left \{ {{4(x+3)-2(y+1)=0} \atop {2(y-1)-(3-x)=-10}} \right. \\ \left \{ {{4x+12-2y-2=0} \atop {2y-2-3+x=-10}} \right. \\ \left \{ {{4x-2y=-10} \atop {x+2y=-10+5}} \right. \\ \left \{ {{4x-2y=-10} \atop {x+2y=-5~~~~-->x=-5-2y}} \right. \\ 4(-5-2y)-2y=-10\\ -20-8y-2y=-10 \\ -10y=-10+20\\ -10y=10~~~~-->:(-10)\\ y=-1\\ x=-5-2 \cdot (-1)=-5+2=-3$

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