Question

f (x) = 4x
g(x) = x + 5

f(x) x g(x)=

4(X) x (X) + 5
4 x 4 x 5 x 4
am i supposed to multiply or add this
16 x 20 im so stuck
x = 320 but that makes no sense
Help please

Answer 1

\(f(x)*g(x)=4x(x+5)=4x^2+20x\)
I suppose u need to find the value of f(x)*g(x) when x=320. Am I right?

Answer 2

are you asking me if thats right?

Answer 3

i got 320, ut i didnt do it like you

Answer 4

what I am asking is what do u need to find?

Answer 5

oh sorry i need to find f(x) x g(x)

Answer 6

it's k:) what is 4 then?

Answer 7

f(x)

Answer 8

right?

Answer 9

u need to find only f(x)*g(x) right? is the value of x given to u?

Answer 10

right, and no

Answer 11

ok fine.:)
f(x) and g(x) are given to you as 4x and x+5 respectively. To find f(x)*g(x) u jst have to multiply them. i.e
f(x)*g(x)=4x(x+5)=(4x*x)+(4x*5)=4x^2+20x. getting this?

Answer 12

yeah

Answer 13

so it would be 36

Answer 14

hw did u get 36?

Answer 15

4 x ^ 2 is 16x + 20 = 36 right?

Answer 16

4x^2 is not equal to 16x.
4x^2=4*x*x
16x=4*4*x
getting the difference?

Answer 17

oh i see so it would be asically 4 + 20

Answer 18

to the power of 2

Answer 19

nope. r u familiar with like terms?

Answer 20

sorry i dont get math

Answer 21

yes i am

Answer 22

gud.:)
Are x and 2x like terms?

Answer 23

yes

Answer 24

gud:)
hw abt x and 2? R they like terms?

Answer 25

no

Answer 26

yup u r right:) remember u can do addition or subtraction only to like terms. If so can u add 2x and 3 and get 5?

Answer 27

no you can't

Answer 28

gud:) one more question
are x^2 and x like terms?

Answer 29

hmmmm... this one is tough i wouldnt think so because their both x, but one is squared and one is nto, ut im still going to say yes they are like terms

Answer 30

but thats wrong isnt it

Answer 31

they are nt like terms. if both the terms are in x then u need to consider the powers. the power of the first one is 2 and the second one is 1 as u said, since the powers are different they are not like terms. for like terms the powers are same.

Answer 32

OH yeah that makes sense

Answer 33

now that u knw they are not like terms is it possible to add x^2 and 2x and get 3x?

Answer 34

no

Answer 35

yup u r right:) is it possible to add 4x^2 and 20x and get 24?

Answer 36

nope i get it now

Answer 37

so i multiply?

Answer 38

no u jst leave it as it is. u need to simplify it only if it is possible.

Answer 39

so now the question is it possible to be simplified?

Answer 40

yup is it possible?

Answer 41

exactly, so i simplify it by

Answer 42

u mean it is possible.?

Answer 43

no it no but in equations that are how do i simplify it

Answer 44

it is not possible to simplify. so u need to leave 4x^2+20x as it is. this because 4x^2 and 20x are not like terms. so u can't add them.

Answer 45

i know but im saying

Answer 46

in another equation how do i simplify

Answer 47

if it can be simplified

Answer 48

sorry im causing u much trouble but thnk you so much

Answer 49

ok say u hav to add 4x and 7x.
as u can see the powers of the x in 4x and 7x are 1. so they are like terms. so u can add them as u would add numbers.
4x+7x=11x

Answer 50

oh i see thnk you so much i get it now

Answer 51

thnk u so much

Answer 52

u r welcome:) nw can u tell what is f(x)*g(x)=?

Answer 53

yup , its 4x(x+5) = (4 x X x ) + ( 4x X 5)= 4 x^2 + 20x

Answer 54

right?

Answer 55

yup right:) gud:)

Answer 56

phew