We will have the following:


So, the solution would be:
Step-by-step explanation:
x > -1
x = {0,1,2,...}

The formula for the area of a triangle is Area=.5(b)(h)
So fill in what you know:
120=.5b*15
Then solve for b.
120=7.5b
b=16
Answer:
6x-21
Step-by-step explanation:
1) draw diagram (in image)
BD=2x-21+4x
combine Like terms
6x-21