Five times the sum of three times a number and 4 is -10, find the number.

Answer 1

Let's use the variable x to represent the unknown number.

The words, " three times a number" would be written as: 3x

The words, " the sum of three times a number and 4: would be written as: (3x + 4).

"Five times the sum" would be represented as: 5(3x + 4)

"Is -10" would be shown as : = -10

Combining all of these expressions gives us the following equation: 5(3x + 4) = -10

This equation can be solved using the distributive property and inverse operations:

5(3x + 4) = -10

15x + 20 = -10

15x + 20 - 20 = -10 - 20

15x = -30

15x/115 = -30 /15

x = -2

The unknown number is -2 .