Find the missing lengths of the sides

Me because some of question i don’t understand

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

Sanjay solved the equation below. which property did he use to determine that 7x+42=42 is equivalent to 7(x+6)=42 7x+42=42 7x=0 x=0