Exponent rule : a^-x = 1/a^x
x^-9 * x^-2 =
1/x^9 * 1/x^2 = (when multiplying exponents with same base, add exponents)
1/x^(9 + 2) =
1/x^11
Let's say the shorter side is x.
So, the longer side would be ( 7 + x )
Now we have to use the Pythagorean Theorem to find the value of x.
a² + b² = c²
( 7 + x )² + x² = 13
7² + x² + x² = 13²
49 + 2x² = 169
2x² = 169 - 49
2x² = 120
x² = 60
x = √60
So the longer side is ( 7 + √60 ) and the shorter side is √60
He lifts for 11 more minuets each day.
51 + 11 = 62
He lifted for 62 minuets on Friday.
62 + 11 = 73
He lifted for 73 minuets on Saturday.
For this case, we have by definition, that an irrational number is a number that can not be expressed as a fraction
, where a and b are integers and b is nonzero.
Some examples are:

So, that the answer is 
Answer:
Option C
Joe is correct because Moe could choose two pieces but had a nine piece variety where as Joe could only choose from 7 pieces of candy