You are talking about the Pythagorean Theorem, correct?
It should be \(\sqrt{15^2+8^2}=c\)
So \(\sqrt{189}=c\)
sqrt(189)=c = c=3*sqrt(21)
I am sorry, but DS is correct! I am human though. But anywho, good job DS!
The answer is 17, btw.
\(c=\sqrt{a^2+b^2}\Rightarrow c=\sqrt{15^2+8^2}\Rightarrow c=\sqrt{225+64}\Rightarrow c=\sqrt{289} \Rightarrow c=17\)
The hypotenuse is 17