80 + ? + -30 = 0 whats in the middle

A50% increase followed by 33 1/2% decrease

If a 36 inch yardstick casts a 21 foot shadow, how tall is a building whose shadow is 168 feet? what is the scale factor

Uestion 1(multiple choice worth 5 points) (05.02)alex wants to paint one side of his skateboard ramp with glow-in-the-dark paint, but he needs to know how much area he is painting. calculate the area of the isosceles trapezoid. isosceles trapezoid with top base 12 feet, bottom base of 18 feet, and height of 6 feet. 72 ft2 84 ft2 90 ft2 108 ft2