Question

simplify (x^2+2x/12x+54)-(3-x/8x+36)

Answer 1

do you know how to subtract fractions?

Answer 2

idk .

Answer 3

all i know what t do is with the denoms

Answer 4

to *

Answer 5

you're right, that gives you the least common multiplier, and in your case it is: (12x+54)(8x+36)

Answer 6

okay , well what do i do with that ?

Answer 7

now divide this with numerator of first fraction, what do you get?

Answer 8

im sorry but im not following with what ur telling me to do . could u show me what u mean? i am genuinely really confused about this .

Answer 9

(x^2+2x/12x+54)-(3-x/8x+36)
=(x^2+2x/12x+54) *(12x+54)(8x+36) - (3-x/8x+36)(12x+54)(8x+36)
do you follow

Answer 10

sure

Answer 11

yea , that makes sense , go ahead .

Answer 12

simplify further:
(x^2+2x)(8x+36) - (3-x)( (12x+54)
now can you open the parenthesis?

Answer 13

like foil ?

Answer 14

yes

Answer 15

sure , h/o

Answer 16

when i foiled i got 8x^3+30x^2+54x+162 , thats without grouping and finding the gcf .

Answer 17

???

Answer 18

close but not yet there
try it this way:

\[x ^{2}(8x+36)+2x(8x+36) - (3(12x+54)-x(12x+54))\]

Answer 19

doesnt it come out to be the same thing ?

Answer 20

lets find out:
\[8x ^{3} +36x ^{2} +16x ^{2} +72x- (36x+162-12x ^{2}-54x)\]

Answer 21

like terms together:
\[8x ^{3} +64x ^{2}+90x-162\]
should be the correct answer

Answer 22

okay , then what happens ? like r the denoms gone now ?

Answer 23

yes, they disappeared when we multiplied by the LCM , the last expression is the answer

Answer 24

okayy then . sorry about me not being able to help much , this stuff just confuses me alot !

Answer 25

practice makes perfect