Martin’s running ability is measured by this proportion: StartFraction 1 over 7 EndFraction = StartFraction 3 over 21 EndFraction Use the proportion to identify the values of the variables that complete the rate table

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.

Set up a system of equations