Question

Find the value of the variable for which the value of the expression –3(2x+1) is 20 greater than the value of the expression 8x+5

Answer 1

Answer:

-2

Step-by-step explanation:

20 greater than 8x +5 is ...

... 8x +5 +20 = 8x +25

We want this value to be -3(2x +1), so we want to solve the equation ...

... 8x +25 = -3(2x +1)

... 8x +25 = -6x -3 . . . . . . eliminate parentheses

... 14x = -28 . . . . . . . . . . . add 6x-25

... x = -2 . . . . . . . . . . . . . . divide by the coefficient of x

The desired value of the variable is -2.

_____

Check

-3(2x+1) = -3(2(-2)+1) = -3(-3) = 9

8x+5 = 8(-2) +5 = -11

9 is 20 greater than -11, so the answer checks OK.