Finding 'A'

this is how to find 'A' in a right-angled triangle:




1. find your formula. in this case, it would be:
-------------->A²=C²-B².

2. substitute 'C' and 'B' with your dimentions.
-------------->A²=15²-8²
-------------->A²=(15x15)-(8x8)<------(know how to multiply with exponents? skip this)

3. calculate.
-->225-64
-->A=the square root of 161
-->A=12.68