Answer:
c) 21
Explanation:
Pythagorean Theorem identified as a^2+b^2=c^2
As a and b can be mixed up, although c will always be the longest side of the triangle.
a) = 7 b) = 14 c) = x
7^2+14^2=x^2
7(7)+14(14)=x^2
49+196=x^2
=
15.65=X
X=16
Can't seem to match with the choices listed. Best to notify the teacher. Without the theorem, process of elimination is best to use.
c) would be the best choice as this is indeed a right triangle.
Other means, it's not too far way from the total of a and b.