At a middle school the ratio of the number girls to the number of boys is 7:4. In the same school, the ratio of the number of boys to the number of teachers is 15:4. If there are 210 girls in the school, find how many teachers are there?

step-by-step explanation:

f(x)=2x^2 -1 

translation is a function transformation that transform the function in a way of translating. by translating the function its graph is moved  up an down. moving the function f(x) 2 units to the left will be the new function g(x) with the equation: g(x)=f(x+2)=2(x+2)^2 -1

the formula of a midpoint between a abd b:

the correct answer would be the third option