Question

-2x-9y=-25
-4x-9y=-23
Help ?!

Answer 1

Turn them into y=mx+b form
(-2/9)x+25/9 and (-4/9)x+23/9.
Then equate them to each other
(-2/9)x+25/9=(-4/9)x+23/9
Then solve of x
(-2/9)x+(4/9)x = (23/9) - (25/9)
X = -1
Then plug in X and solve for y
Y = (-2/9)(-1) + (25/9)
Y= (27/9)
Y= 3
So your solution is (-1,3)

Answer 2

Its solve the system of equations. you can do substitution or elimination.

There are two kinds of solving but elimination seems best for this system:

-2x-9y=-25
4x+9y=23 (multiplied it by -1 so you can eliminate the variable "Y")
---------------
2x=-2
x=-1 (divide by 2 on each side)

-2(-1)-9y=-25 (insert what you received for what "X" is)
2-9y=-25 (simplify)
-9y=-27 (subtract 2 on each side)
y=3 (divide each side by -9)