function question college algebra

Question

Given 

a) Evaluate 

b) Solve 

x=

Answer 1

Hello, thank you for taking the time to post your question!

If you have f(x) = 4x + 5, that means that

f(-5) = 4(-5) + 5 = -20 + 5 = -15

then for the second part of the question you would set it equal to 9 and then solve

4x + 5 = 9

4x = 4

x = 1

I hope that helps you get moving in a better direction on this type of question! Feel free to reach out if you have any additional questions beyond that :)

Answer 2

Given f(x)=4x+5

a) Evaluate f(−5)

f(−5)= 4(-5)+5

= -20+5

= -15

b) Solve 

f(x)=9

since f(x) = 4x+5

substitute the value in above function

4x+5=9

4x =9-5

4x =4

x=1

Hence the value of x=1