The sum of the supplement of one angle and it compliment is 210°. Find the measure of the angle

In the 30-60-90 triangle below side s has a length of and side r has a length

The first floor of marcus’ house is 1,440 square feet. he will cover 1,033 square feet with wood and the rest with tile. a box of tiles will cover 11 square feet. how many boxes of tile does marcus need to buy to cover the floor?

Can someone factor this fully? my friend and i have two different answers and i would like to know if either of them is right. you in advance. a^2 - b^2 + 25 + 10a