-5 is the answer to your question because all you do is plug in -2 into your equation for x
Answer:
Step-by-step explanation:
In order to do this we need to isolate y by performing the inverse operations on the other values like so...
a) 10x + 5y = 20 ... subtract 10x on both sides
5y = 20 - 10x ... divide both sides by 5
y = 4 - 2x ... we can move the 2x to the right to make it into y = mx + b
y = -2x + 4
b) 3x - 2y = 10 + 4x ... subtract 3x on both sides
-2y = 10 + x ... divide both sides by -2
y = -5 - 0.5x ... move -0.5 to the left so it matches y = mx + b
y = -0.5x - 5
