Answer:
1. 2x + y = 5
y = -2x - 5
2. x^2 + y^2 = 5
sub 1. into 2.
x^2 + (-2x - 5)^2 -5 = 0
x^2+ 4x^2 - 20x + 25 - 5 = 0
5x^2 - 20x + 20 = 0
5(x^2 - 4x + 5) = 0
5(x-2)^2 = 0
x = 2
sub x into 1.
2(2) + y = 5
y = 1
x = 2, y = 1
Step-by-step explanation:
See 2x + y = 5 as equation 1, and see x^2 + y^2 = 5 as equation 2.
Isolate equation 1's y, and sub the equation into equation 2.
The common factor of the new equation is 5, which divides the whole thing by 5, then find the answer, and further sub the answer into the equation 1 since it is easier to do so, therefore, the answer is x = 2, y = 1.
