43 cents written as a percent of $1 can be written as..

There are 15 plates and each plate is either 7 or 12 inches diameter. which systems of equations do you use to find the number of 7 inch plates, x and 12 inch plates, y

The length of a shadow of the building is 36m. the length of the pole, which is perpendicular to the ground, is 1.9m. the length of the pole's shadow is 1.52m. what is the height of the building?

Angles r and s are complementary. the measure of angle r is 31 degrees. which equation can be used to find angle s?