Complete the following for each system that involves one or more quadratic equations:

Solve the system algebraically

7y^2-5x^2+20x=3
5x^2+21y^2=209

2 answers

eq #1 says that 7y^2=5x^2-20x+3, so plug that into eq #2 and you have

5x^2+3(5x^2-20x+3) = 209
20x^2-60x-200 = 0
x^2-3x-10 = 0
(x-5)(x+2) = 0

And I think you can take it from there, no?
yes, thanks i can :)