Simplify 9 to the 2nd over 9 to the 7th. a 95 b 1 over 9 to the 9th c 1 over 9 to the negative 5th d 1 over 9 to the 5th

9^2/9^7

when dividing powers, we subtract the exponents

9^(2-7)

9^ (-5)

a negative exponent flips from the numerator to the denominator

1/ 9^5

Choice D

if x decreases by 4 then y increases by 10

step-by-step explanation:

pi x^2

step-by-step explanation:

pi times x squared