The output of a function is 7 more than times 3 the input. find the input when the output is - 8

Let the output = Y and the input = X.

The output (y) is 7 more than 3 times the input (x), which can be written as an equation:

Y = 3X+7

The out put is - 8, so replace Y in the equation and solve for X:

-8 = 3X+7

Subtract 7 from each side:

-15 = 3X

Divide both sides by 3:

X = - 15 / 3

X = - 5

The input is - 5