-5x-10=10 x= -4
Work:
-5x-10=10
+10 +10
______________
-5x=20
_______
-5 -5
x=-4
I would solve this using tangents. Let h be height of flagpole.
Set up 2 right triangles, each with a base of 40.
The larger triangle has height of "h+70"
Smaller triangle has height of 70.
Now write the tangent ratios:

Note: A-B = 9
To solve for h we need to use the "Difference Angle" formula for Tangent

Plug in what we know:



Answer:
a. pi
Step-by-step explanation: