Answer:
Point D is the solution to the system of equations.
Explanation:
When asked for a solution involving 2 equations, the goal is to find a point (x,y) that would be a solution to both equations. Any point on a line that is defined by an equation is a solution to that equation. For an equation of y = 2x + 2, possible solutions are (1,4), (2,6), (5,12) etc. These points all lie on the line formed by that equation. There are an infinite number of possible solutions. If a second eqaution is added, there is now a constraint on the possible answers. The goal is to find a point that satisfies both equations.
If a seond equation of y = 1x + 3 were matced with y=2x+2, both are straight lines, but with different slopes. So they will intersect at some point. One may either solve mathematically using substitution, or by graphing, as was done here.
Matematically:
y = 2x + 2
y = 1x + 3
Rearrange either equation to isolate a variable, x or y. These are already isolated (since I made them up) so go to the next step of substituting one expression of y into the other:
y = 1x + 3
2x + 2 = 1x + 3
x = 1
Now use this value of x to find y:
y = 2x + 2
y = 2*(1) + 2
y = 4
The point these two lines intersect is (1,4) and is the "solution" to this series of equations.
See the attached graph.