6.
To find this, follow these steps:
a = 1/2bh
15 = 1/2 x 5 x h
First, multiply the left side of the equal sign by 2 to get rid of the 1/2.
After you do this, you should have this:
30 = 5h
Now, divide both sides by 5 to find your final answer for h which is 6.
Hope this helps!
