Question

3 times 21 more than a number is 12. What is the number?

Answer 1

Answer: x = -17

Form your equation, where x is the number.
3(x + 21) = 12

Solve for x.
3(x + 21) = 12 Distributive Property
3x + 63 = 12 Subtract 63 from both sides
3x = -51 Divide by 3 to both sides
x = -17 Answer!

Answer 2

Turn it into an equation then solve.

3 (x + 21) = 12
3x + 63 = 12
3x = -51
x = -17