Question

In the system shown below, what is the sum of the x-coordinates of all solutions?

3y^2-5x^2=7
3y^2-x^2=23

Answer 1

The sum of the x coordinates is 0.

Explanation:

3y^2-5x^2=7

3y^2 =x^2 + 23

-4x^2 = -16

x^2 = 4

x= -2, 2

2-2=0

Answer 2

we are given the equation 3y^2-5x^2=7 and 3y^2-x^2=23. there are two equations two unknowns hence the problem can be solved.

3y^2-5x^2=7
3y^2 =x^2 + 23

x^2 + 23 = 7 + 5x^2
4x^2 = 16
x^2 = 4
x1 =2
x2 = -2

sum is 2-2 = 0