There are two questions I'm completely lost with.

0.9t = 1+ t.

It seems fairly straightforward, but I divide the problem by t and from there it makes no sense. Every answer I come out with, when I check it it doesn't fit.

x/(x2-9) + 4/(x+3) = 3/(x2-9)

What I do is divide all three parts by x2 -9. From there I get x + 4/(x3 - 3x2 - 9x - 27) = 3 And I don't know what to do at all! Could someone help me and explain the process... or tell me what I'm doing wrong? Thanks in advance...

I don't understand the second Q but when I do the first one I end up wit -2 which doesn't work

First question = -10.
0.9t - t = 1
-0.1t = 1
t = 1/-0.1
t = -10.

Second question = * provided you did give the question correctly *
can only be simplified to x^2 + 8x - 45.

Multiply 2x - 9 on both sides
= x + (2x-9)*4/x+3 = 3
therefore:
3 - x = (8x-36)/x+3

And thus multiply x+3 on both sides.
Which results:
9 - x^2 = 8x - 36
Simplified to: x^2 +8x - 45 =0