What is one of the solutions to the following system of equations? y2 + x2 = 53 y − x = 5 (−10, −5) (−7, −2) (7, 2) (5, 10)

Question

What is one of the solutions to the following system of equations?  y2 + x2 = 53 y − x = 5   (−10, −5)   (−7, −2)   (7, 2)   (5, 10)

campbell_st · Answer

well I'd use substitution 

take the 2nd equation and make y the subject.. 

y = x + 5

and substitute it into the 1st equation 

$$x^2 + (x + 5)^2 = 53$$

then you get after simplifying 

$$2x^2 + 10x -28 = 0$$

divide each term by 2

and you have 

$$x^2 + 5x - 14 = 0$$

just solve by factoring... and you'll get 2 solutions

campbell_st · Answer

but only 1 answer is shown in your choices.