Question

Tolong Dibantu Teman Teman No 1 Sampai 22 Pakai Cara

Answer 1

1) 3x-2y = 6
jika x = 0 → 3.0-2y = 6
-2y = 6
y = 6/-2
y = -3
didapat ttk.(0,-3)

jika y = 0 → 3x-2.0 = 6
3x = 6
x = 6/3
x = 2
didapat ttk.(2,0)
jadi, jwbnnya (A)


2) C.(i),(iii),(iv)


3) A(-2,3) dan B (-4,-5)
gradien (m) = y2-y1/x2-x1
= -5-3/-4+2
= -8/-2
= 4 ...(D)


4) 2x+5y-4 = 0
a = 2 , b = 5
m = -a/b
= -2/5 ...(B)


5) D.1,2,3,4


6) 7x+4y = 16
a = 7 , b = 4
gradien tegak lurus :
m = b/a
= 4/7 ...(C)


7) pers.grs.melalui ttk.(0,-4) dan m = -3/4 :
y-y1 = m.(x-x1)
y+4 = -3/4.(x-0)
kdua ruas dikalikan dg 4 menjadi :
4 (y+4) = -3.(x-0)
4y+16 = -3x
3x+4y+16 = 0 ...(C)


8) pers.grs. melalui (-2,4) dan (6,3) :
y-y1/y2-y1 = x-x1/x2-x1

y-4/3-4 = x+2/6+2

y-4/-1 = x+2/8

kdua ruas dikalikan silang menjadi :
-1.(x+2) = 8.(y-4)
-x-2 = 8y-32
8y+x-32+2 = 0
8y+x-30 = 0 ...(C)


9) 3x-4y = 8
a = 3 , b = -4
gradien sejajar :
m = -a/b
= -3/-4
= 3/4
jadi, pers.grs.melalui ttk.(4,-5) dan m = 3/4 :
y-y1 = m.(x-x1)
y+5 = 3/4.(x-4)
kdua ruas kalikan dg 4 menjadi :
4.(y+5) = 3.(x-4)
4y+20 = 3x-12
4y = 3x-12-20
4y = 3x-32
y = 3/4 x - 32/4
y = 3/4 x - 8 ...(C)


10) y = 1 1/2 x - 2
y = 3/2 x - 2
jika x = 0 → y = 3/2.0 - 2
y = -2
didapat ttk.(0,-2)

jika y = 0→ 0 = 3/2 x - 2
0+2 = 3/2 x
2 = 3/2 x
x = 2 : 3/2
x = 2 . 2/3
x = 4/3
x = 1,33
didapat ttk.(1,33 ; 0)

jadi, jwbnnya (A)



11) x+2y-6 = 0
x+2y = 6
utk x = 0 → 0+2y = 6
2y = 6
y = 6/2
y = 3
didapat (0,3)

utk x = 2 → 2+2y = 6
2y = 6-2
2y = 4
y = 4/2
y = 2
didapat (2,2)

utk x = 4 → 4+2y = 6
2y = 6-4
2y = 2
y = 2/2
y = 1
didapat (4,1)

jadi, jwbnnya (C)



12) 2y-x = 6
y = x+3 atau y-x = 3
dr kdua persamaan tsb dieliminasi sbb :
2y-x = 6
y-x = 3
________ -
y = 3 → y-x = 3
3-x = 3
-x = 3-3
-x = 0
x = 0
jadi, HPnya = {(0,3)} ...(A)



13) 3x-4y = -6 |x1| 3x-4y = -6
6x-2y = 6 |x2| 12x-4y = 12
____________ -
-9x = -18
x = 18/9
x = 2

x = 2 → 6x-2y = 6
6.2 - 2y = 6
12 - 2y = 6
-2y = 6-12
-2y = -6
y = 6/2
y = 3
jadi, HP nya : {(2,3)} ...(D)



14) K = 72
p = 4+l
maka :
K = 2.(p+l)
72 = 2.(4+l + l)
72:2 = 4+2l
36 = 4+2l
36-4 = 2l
32 = 2l
l = 32/2
l = 16 cm → p = 4+l = 4+16 = 20 cm

jadi, L = p.l
= 20.16
= 320 cm² ...(D)



15) 4x-5y = -9 |x1| 4x-5y = -9
2x+3y =23 |x2| 4x+6y = 46
___________ -
-11y = -55
y = 55/11
y = 5

y = 5 → 2x+3y = 23
2x+3.5 = 23
2x+15 = 23
2x = 23-15
2x = 8
x = 8/2
x = 4

jadi, HP nya : {(4,5)} ...(A)

Answer 2

Semoga membantu, jawaban ada di file doc