Find the mean of the table below

Solve the system of equations y= 3/2 - 1, -x+ y =-3

Let hh represent the number of hummingbirds and ss represent the number of sunbirds that must pollinate the colony so it can survive until next year. 6h+4s > 746h+4s> 74 this year, 88 hummingbirds pollinated the colony. what is the least number of sunbirds that must pollinate the colony to ensure that it will survive until next year?

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