Question

How do you find the value of x so that the function n(x) = 7x +4 has the given value 39?

Answer 1

`x=5`

Explanation:

the function has a value of 39 when n(x)=39, therefore we can substitute 39 instead of n(x) and solve for x

`n(x)=7x+4`
`39=7x+4`
`7x+4=39`
`7x+4-4=39-4`
`7x=39-4`
`7x=35`
`(7x)/7=35/7`
`x=5`

you can check your answer by plugging the value of `x` back into the original function and seeing if the n(x) value is 39

`n(x)=7x+4`
`n(5)=7(5)+4`
`n(5)=35+4`
`n(5)=39`

`:.` the answer is correct