Question

Solve the system by the substitution method. Show your work.
2y - x = 5
x^2 + y^2 - 25 = 0

Answer 1

2y - x = 5
x^2 + y^2 - 25 = 0

x = 2y - 5

(2y-5)^2 + y^2 - 25 = 0
(2y-5)(2y-5) + y^2 - 25 = 0
4y^2 - 20y + 25 + y^2 - 25 = 0
5y^2 - 20y = 0
y = 0 , y = 4

x = 2y - 5 , when y = 0
x = - 5

x = 2y - 5 , when y = 4
x = 8 - 5
x = 3