Answer is A
The binomial can be factored using the difference of squares formula a2-b2 = (a+b) (a-b) where a=x and b=9
(X+9) x(x-9)
You'd want to buy the 4 by 5 and the 11 by 14 because if you times 4 by 3 and 5 by 3, the answer would be 12 by 15 which is the closet or the most similar pair
3⁴-21÷7
According to PEMDAS ( order of operations):
First, Do exponents before multiplying or dividing: 3^4
81-21÷7
Then, divide before subtracting (27÷7 )
81- 3
Finally, subtract
78