How do you evaluate this system of equations: y-2x=-5; y-x=-3?
1 Answer
Jun 14, 2017
Explanation:
- To solve this specific system, the easiest method is substitution.
y-2x=-5
y-x=-3 - Choose one of the equations .. I will pick
y-x=-3 . - The objective is to get one of the variables (
x ory ) by itself on one side of the equation .. Pick a variable to isolate .. I will picky . - To isolate
y , ADDx to both sides of the equation:
y-x=-3
y=-3+x - Look at the OTHER equation (the one you did not choose) .. That would be
y-2x=-5 for me.
See howy is EQUAL to(-3+x) ?
You can substitute they iny-2x=-5 with(-3+x)
It should look like this:(-3+x)-2x=-5 - SIMPLIFY! Now we only have ONE variable in the equation.
(-3+x)-2x=-5
-3-x=-5
-x=-2
x=2 [THIS IS THE ANSWER FOR X] - Take one of the equations and substitute
x for2 to solve fory .
y-2x=-5
y-2(2)=-5
y-4=-5
y=-1 [THIS IS THE ANSWER FOR Y]
If your teacher wants it as