Three consecutive integers have a sum of - 21. Which equation can be used to find the value of the three numbers?

a. x+x+x = - 21

b. x+2x+3x = - 21

c. x + (x+1) + (x+2) = - 21

d. x + (x+2) + (x+4) = - 21

c. x + (x+1) + (x+2) = - 21

Step-by-step explanation:

Consecutive integers are in a row, like 1,2,3

Let x = the first integer

The next integer is 1 ahead of it

x+1 = next integer

Add 1 to move to the 3rd integer

x+1+1 = x+2

x+2 = the 3rd integer

Add the 3 integers

x + (x+1) + (x+2) = - 21