How to solve this equation?
X^2=20

Imagine a new pasture with grass growing on it. every day after the seeds have germinated, the number of blades of grass in the pasture triples. after 18 days, the entire pasture is completely covered in grass. how many days did it take for the pasture to be one-third covered in grass?

Evaluate the expression for the given value of the variable. 5×(h+3) for h=7

He that is measured at 220° is a reflex angle. the opposite angle is obtuse. find the measure of obtuse .