Solve for r.
You want to get r by itself on one side on the equal sign.
bh + hr = 25
Subtract bh from both sides.
hr = 25 - bh
Divide h on both sides.
r = 25 - bh / h
The two h's cancel each other out.
r = 25 - b
Hope this helps!
6.) constant = 75
7.) open sentence = 6 + 22 = 28
8.) equation = 17 + b = 47
9.) solution = when x + 37 = 62, x = 25
Answer:
6 : 23
Step-by-step explanation:

1st :The angle of depression 30° = the angle of elevation (from the truck to the height of the building.
2nd :
cos 30° = (adjacent side)/(hypotenuse)
cos 30° = x/100, but cos 30°= (√3)/2
(√3)/2 = x/100 and x = (100√3)/2
and x = (50.√3) = 86.60 m