Question

Try the numbers 9, 10, 11, 12 in the equation 60 − 3 ⋅ z = 30

to test whether any of them is a solution.
a. 11 is a solution. c. 12 is a solution.
b. 10 is a solution. d. 9 is a solution.

Answer 1

10 is a solution.

Explanation:

• Step 1: Equation is 60 - (3 × z) = 30 Substitute values of 9, 10, 11 and 12 to find the solution.

When z = 9, 60 - (3 × z) = 60 - (3×9) = 60 - 27 = 33 ≠ 30

When z = 10, 60 - (3 × z) = 60 - (3×10) = 60 - 30 = 30

When z = 11, 60 - (3 × z) = 60 - (3×11) = 60 - 33 = 27 ≠ 30

When z = 12, 60 - (3 × z) = 60 - (3×12) = 60 - 36 = 24 ≠ 30

⇒ 10 is a solution.