Given that A=1/2(b+B)h. Use the values A=81, b=10 and B=17 to find h.

A. 54
B. 170
C. 6
D. 13.5

Can you explain how to get the answer?
Answer: C

h=2A/(b+B)=2*81/(10+17)=6

Right, just one point. Your formula, as written, is ambiguous. Is it

A = 1 / [2(b+B)h]

or is it

A = (1/2) * (b + B)h
I'll assume that this one is what you meant. The first thing I would do is to rearrange the formula so that we have h on one side of the equation and everything else on the other.

First step is to get rid of the (1/2) so I'll multiply both sides by 2 to get...

2A = (b + B ) h

Now divide both side by (b + B) to get h on its own

h = 2A / (b + B)

Now, replace the letters with the number that we have been given.

h = 2 (81) / (10 + 17) = 162 / 27 = 6
So
h = 6, making answer C. correct.

Hi,
It is quite simple.
A=1/2*(b+B)*h
Now put the given values
81=1/2*(10+17)*h
81=1/2*(27*h)
81=(27*h)/2
81*2=27*h
162=27*h
h=162/27
h=6.
Answer

A = 1/2(b + B)h.
h = 2A/(b + B)
If A = 81, b = 10 and B = 17,
h
= 2*81/(10 + 17)
= 162/27
= 6
Answer:
C. 6

81 = (27h)/2
162 = 27h
h = 6

C