Fine the x, and y
x = 8 − 2y
y − x = 4
Hint: Because one of the equations above is already solved for x, one strategy to solve this system is to substitute the first equation in for x in the second equation
Fraction in the first one -1/2, and find x,y.
y= -1/2x+7
y=x-8
The hint they gave you is a good one. x is equal to "8 - 2y", which is already half-solved for us. Take your second equation, and replace the "x" variable with what it's equal to:
y - x = 4 y - (8 - 2y) = 4 y - 8 + 2y = 4 y + 2y = 8 + 4 3y = 12 y = 4
Now that we know the exact number for y, we can plug this back into our first equation:
x = 8 - 2(4) x = 8 - 8 x = 0
You always want to check your answers to make sure they're right. If y = 4 and x = 0, then....
