
Matt W. answered 04/04/19
Cornell Math and Science Tutor with Engineering Background
Happy to help!
A solution to a system of equations means to find the values for x and y where the functions are equal. In this case we have two functions:
y = 2
and
y = x2 + 5x + 6
So let's set them equal to each other and see what happens:
2 = x2 + 5x + 6
Let's rearrange the equation by subtracting two from each side:
0 = x2 + 5x + 4
Does it look familiar yet? It's a quadratic equation! We need to factor this right away...
0 = (x+4)(x+1)
So what values of x make the equation equal zero? Let's try x = -4
0 = (-4 + 4)(-4+1) = 0(-3) = 0
Okay that worked. We could also have found the first solution for x by solving:
x+4 = 0
The second solution can be found by solving:
x+1 = 0
So together, the x values are x = -4 and x = -1. We already know that these values occur at y = 2.
The final answer could be written as (-4, 2) and (-1, 2)
Hope that helps