Question

What are the x-coordinates of the solutions to this system of equations?

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

Answer 1

Replace y in the first equation with (2x-5) from the second equation and solve for x.
You will get a quadratic equation in x with two solutions.
Put each x in the second equation and find the corresponding y's.
Express your answer in the form (x,y)

Answer 2

x^2 + (2x-5)^2 = 25
that right so far? @ranga

Answer 3

Yes. Expand (2x-5)^2. Add like terms. Bring the 25 from the right to the left and solve the quadratic equation.