The x intercept of a graph is the point where y=0 so the point is (x,0)
To find the x intercept of a line, set y to 0 and solve for x.
0=(1/3)x+7
subtract 7
-7=(1/3)x
multiply by 3
-21=x
so the x intercept is (-21,0)
0=2x+5
subtract 5
-5=2x
divide by 2
-2.5=x
and the x intercept is (-2.5,0)
Add the x intercepts together:
-2.5+-21=\(\boxed{-23.5}\)