Find the measure of ab if c is the midpoint of ab ac=6x-20 and cb=4x-12

Me. i can't figure out this question. give an explanation too. .

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'

Compare the following pair of numbers a and b in three ways. a. find the ratio of a to b. b. find the ratio of b to a. c. complete the sentence: a is percent of b. a=120 and b=340 a. the ratio of a to b is . b. the ratio of b to a is . c. a is nothing percent of b.