What is the value of x in trapezoid abcd

What should be done to solve the equation? x+14=21 add 14 to both sides of the equation. subtract 14 from the left side of the equation. add 14 to the left side and subtract 14 from the right side of the equation. subtract 14 from both sides of the equation.

Ling listed all of the factors of a mystery number: 1,2,4,8,16,32 what is the mystery number?

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10