If f(x)=4x-11 what is the value of f(5)

f(5) = 4(5) - 11

f(5) = 20 - 11

f(5) = 9

The answer is 9 :)

Please give BRAINIEST :)

Thanks

9

Step-by-step explanation:

Call the Total Amount of money he had X.

Amount he used to buy pens: 3/8X

Amount of money left after buying pens: X - 3/8X = 5/8X

Amount he used to buy notebooks: 2/5 * 5/8X = 1/4X

1/4X or 2/8X for 2 notebooks, so if he spent 3/8X for notebooks, he would get 3 notebooks.

As a notebook cost 3 times a pens, so for 3/8X money, he bought 9 pens.