the sum of two numbers is 30. the difference of their squares is 180. find the two numbers by elimination method

1 answer

Let x = one number and y = second number

Hint:
Equation #1: x+y=30
Equation #2: x^2 - y^2 = 180

x = 30-y
(30-y)^2-y^2=180
y^2-60y+900-y^2=180
-60y=-720
y=12
x = 30-12
x=18