It appears that both of these equations are in y=mx+b form, also known as slope-intercept form.
In this, m = slope and b = y-intercept, while x and y are the x and y values.
In the top equation (y = x + 3), the slope is 1 and the y-intercept is 3.
In the bottom equation (y = 2x + 5), the slope is 2 and the y-intercept is 5.
If this is a system of equations, you would solve it by figuring out where the lines intersect.
You can do this by graphing or by using the substitution or elimination method.
I find it easiest to graph, as there are a lot of steps to the substitution or elimination methods.
When you graph this system of equations, you are left with the lines intersecting at (-2, 1), which is the solution.
Hope this helps :)