Question

What are the solutions of the following system?

=
[x2 + y2 = 25
2x+y=-5
(0, -5) and (-5,5)
(0, -5) and (5, -15)
(0, -5) and (-4,3)
O (0,-5) and (4, -13)
What is it?

Answer 1

Third option: (0,-5) and (-4,3)

Explanation:

x^2 + y^2 = 25

2x + y = -5

y = -5 - 2x

x^2 + (-5-2x)^2 = 25

x^2 + 25 + 20x + 4x^2 = 25

5x^2 + 20x + 25 = 25

5x^2 + 20x = 0

5x(x+4) = 0

5x=0 --> x=0

x+4=0 --> x=-4

2(-4) + y = -5

-8 + y = -5

y = 3 --> (-4,3)

2(0) + y = -5

0 + y = -5

y = -5 --> (0,-5)

Therefore, the solutions to the system of equations are (0,-5) and (-4,3)