10p+9p=12 solve this for me with work shown

What is the answer to this question? i'm a bit stumped. also how do i do it? 5(x - 4) = 2(x + 5)

Aresearch group wants to find the opinions’ of city residents on the construction of a new downtown parking garage. what is the population of the survey downtown shoppers downtown visitors downtown workers city residents

Ahiker stands at an unknown elevation before he ascends 2 miles up a mountain to an elevation of 9 miles. find the elevation of the hiker before his ascent.