Question

Help please! my username is mathdummy for a reason!...Find constants A and B that make the equation true
2x-9/x^2- x- 6 = A/x-3 + B/x+2

Answer 1

lol smoothmath you probably think im a true math idiot by now

Answer 2

First off i would like you to factor the denominator of the left hand side

Answer 3

^What he said

Answer 4

can't i multiply to set the denominators equal first?

Answer 5

i see nothing suspicious in asking questions from substitution to calculus and then to partial fractions..

Answer 6

if you can see it go ahead but i think that might be complicating the scenario

Answer 7

lol @lgbasallote

Answer 8

look igbasallote idk what to tell ya..if you don't believe me or dont want to believe me fine..but trust me when i say im not getting on here and asking math questions for fun...im taking several online courses and this just happens to be whats thrown at me

Answer 9

Interesting.

Answer 10

after you factor, and then multiply the denominator, you should have something like this

2x - 9 = A(x+2) + B(x-3)

Answer 11

Do you understand how i got to that step

Answer 12

ya that makes sense to me...

Answer 13

now, the next step will be to distribute the A and the B

Show me what you get when you finish

Answer 14

2x-9 = Ax + 2A + Bx - 3B....
2x = Ax + Bx
-9 = 2A - 3B
2 = A + B
-9 = 2A - 3B
6 = 3A + 3B
-9 = 2A - 3B +.....am i doing this right so far??

Answer 15

Looks right

Answer 16

yes

Answer 17

At this point,

2 = A + B
-9 = 2A - 3B

we can do substitution.

2 = A + B, can be written as ;

A = 2 - B

Answer 18

then substitute A into the other equation ( -9 = 2A - 3B )

Answer 19

try it it should be easy from here. First you will get B. And then you can solve for A

Answer 20

Okay so for my final answer i got B = 13/5 and A = 3/5...look right?

Answer 21

yes

Answer 22

thanks so much for your help!!

Answer 23

Anytime