Question

In the function f(x) = 6x + b, what must be the value of b, if f(5) = 1?

Answer 1

Answer:

Step-by-step explanation:

f(5) = 1

6*5 + b = 1

30 + b = 1

b = 1 - 30 = -29

b = -29

Answer 2

Answer:    -29

=============================================

Work Shown:

f(x) = 6x + b

f(5) = 6(5) + b .... replace every x with 5

f(5) = 30 + b

1 = 30 + b ..... replace f(5) with 1, since f(5) = 1 was given.

1-30 = 30 + b - 30 .... subtract 30 from both sides

-29 = b

b = -29

-----------

The function f(x) = 6x+b turns into f(x) = 6x+(-29) which is equivalent to f(x) = 6x-29

Plugging in x = 5 leads to

f(x) = 6x-29

f(5) = 6(5) - 29

f(5) = 30 - 29

f(5) = 1

So we have confirmed the answer.