Question

What are the solutions to the following system of equations?
y = x2 + 3x − 7
3x − y = −2

Answer 1

The answer choices are
(3, 11) and (−3, −7)
(11, 3) and (−3, −7)
(3, 11) and (−7, −3)
No real solutions

Answer 2

I would solve using substitution, since you are already given what y equals in the first equation.

You know y = x^2 +3x -7, so you can plug that value of y into the second equation giving you:

3x - y = -2
3x - (x^2 + 3x -7) = -2
-x^2 + 3x - 3x +7 = -2
-x^2 +7 = -2
-x^2 = -9
x^2 = 9
x = (+-)sqrt(9)

Answer 3

now that you've solved for x, you can plug that value back into either original equation to solve for y! Give it a shot!

Answer 4

so it would be y=\[\sqrt{9}^{2}+3\sqrt{9}-7\]

Answer 5

so its plus or minus square root of 9, so you can simplify that to -3 and +3. but otherwise yes, thats perfect!

Answer 6

Thanks