Question

For the function f(x) = 5x^2 + 3x - 8. What is the value of the function when x=3 ?

Answer 1

The answer is 46. Hopefully this explains it good for you. All you do is substitute X for 3, and then solve using PEMDAS.

Hope this helps :)

Answer 2

46

Explanation:

`f(x) = 5x^2 + 3x - 8\\x =3\\\\= 5(3)^2+3(3)-8\\\mathrm{Follow\:the\:PEMDAS\:order\:of\:operations}\\\\\mathrm{Calculate\:exponents}\:\left(3\right)^2\::\quad 9\\=5\cdot \:9+3\left(3\right)-8\\\\\mathrm{Multiply\:and\:divide\:\left(left\:to\:right\right)}\:5\cdot \:9\::\quad 45\\=45+3\left(3\right)-8\\\\\mathrm{Multiply\:and\:divide\:\left(left\:to\:right\right)}\:3\left(3\right)\::\quad 9\\=45+9-8\\\\\mathrm{Add\:and\:subtract\:\left(left\:to\:right\right)}\:45+9-8\:\\:\quad 46`