This is what I was given:
x+y=11
x² - y² = 77
I need to find x. How do I do this?
Do I square the x+y=11 and then add the two equations to find x?
Find out what x or y equals in one of the equations and then substitute it into the second equation. This gives you the value of one variable. Then just plug that value into one of the original equations to find the other variable:
EX:
x + y = 10
2y - 2x = 0
x = -y + 10
2y - 2(-y + 10) = 0
2y + 2y - 20 = 0
4y = 20
y = 5