Question

I need help with question 26
this is from my physics textbook

Answer 1

Suppose
`a,b,c` are measured in meters. Then the semiperimeter
`s=\frac{a+b+c}2` is also given in meters, so
`s-a,s-b,s-c` are all also given in meters. When multiplied together,
`(s-a)(s-b)(s-c)` is measured in cubic meters. Divide this by
`s`, measured in meters, and this reduces to square meters. Take the square root and you end up back with meters once again. So the formula is indeed dimensionally consistent.