Hello!
You can use this by using the Pythagorean theorem
[tex] a^{2} + b^{2} = c^{2} [/tex]
c is the hypotenuse which is the angle opposite the right angle
a and b are the other two sides
you put the values in that you know
[tex] 72^{2} + b^{2} = 78^{2} [/tex]
square the numbers
5184 + [tex] b^{2} [/tex] = 6084
Subtract 5184 from both sides
[tex] b^{2} [/tex] = 900
Take the square root of 900
square root of 900 = 30
The answer is 30
Hope this helps!
