Question

http://www.corealgebra.com/Auth/Unit12/gifs/u12s4t2p3.gif

Answer 1

Hi, sorry I couldn't get to you earlier :/

to do this you'll have to understand that multiplying 1/(a-4) by (a-4) gives you 1
like how 1/3 times 3 = 1

so to get rid of all the denominators, you have to multiply each value by 9(a-4)
since one of the denominators is a-4 and the other is 9

so 1/(a-4) times 9(a-4) = 9

4/9 times 9(a-4) = 4(a-4)

and a times 9(a-4) = 9a(a-4)

so you get 9 + 4(a-4) = 9a(a-4)

you would then distribute

so 9 + 4a - 16 = 9a^2 - 36 (add like terms)

4a - 7 = 9a^2 - 26 subtract 4a from both sides

9a^2 - 4a - 26 = -7 add 7 to both sides

9a^2 - 4a - 19 = 0