Help please i dont understand

How can you decide witch operations to use to slice a two step equation

Merrida uses a pattern in the multiplication table below to find ratios that are equivalent to 7: 9. if merrida multiplies the first term, 7, by a factor of 6, what should she do to find the other term for the equivalent ratio? multiply 9 by 1. multiply 9 by 6. multiply 9 by 7. multiply 9 by 9.

Mis the midpoint of rq if rm equals 2x + 5 and mq equals 4x - 9 what is the length of rq