{-4x+2y= -18
{-2x=y+5
2007-03-07 02:51:14 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
considering eqn 1
-4x = -18 -2y
dividing by 2
-2x = - 9 -y
-2x+9 = -y
substitute this value of y in eqn 2
-2x= 2x-9 +5
4x=4
x=1
hence y =-7
2007-03-07 02:57:36 · answer #1 · answered by Tasha 2 · 0⤊ 1⤋
-2x = y + 5
> y = -2x - 5 = -(2x + 5)
-4x + 2y = -18
> 4x - 2y = 18
> 4x + 2(2x + 5) = 18
> 4x +4x = 18 - 10
> x = 8/8
> x = 1
y = -(2*1 + 5)
= -7
2007-03-07 10:58:36 · answer #2 · answered by ganesan 2 · 0⤊ 0⤋
-4x+2y=-18
-4x = -2y -18
x = 1/2 y + 9/2 --(1)
-2x=y+5
from(1)
-2(1/2 y +9/2) = y+5
-y - 9 = y + 5
2y = -14
y = -7
Substitute into (1)
x = 1/2(-7) +9/2
x = 1
2007-03-07 10:56:05 · answer #3 · answered by seah 7 · 0⤊ 0⤋
Solve the 2nd equation for Y and then substitue that answer into the 1st equation and solve for X. Enter the value for X into either equation and solve for Y.
This will get you started (the 2nd equation solved for Y would be:
y = -2x-5
Substitute -2x-5 for Y in the first equation and solve for x.
Good luck
2007-03-07 10:59:49 · answer #4 · answered by Kenny 3 · 0⤊ 0⤋
-2x=y+5
y=-2x-5
-4x+2y=-18
-4x+2(-2x-5)=18
-4x-4x-10=18
-8x=28
x=-7/2
y=-2x-5
y=-2(-7/2)-5
y=7-5
y=2
2007-03-07 10:56:27 · answer #5 · answered by eriq p 4 · 0⤊ 1⤋