Advanced algebra help !!!

please explain what needs to be done and Iwill pick best thnx

Mary is reviewing her algebra quiz. She has determined that one of her solutions is incorrect. Which one is it?

A. 2x + 5 (x-1) = 9, x = 2
B. p - 3(p-5) = 10, p = 2.5
C. 4 y + 3 y = 28, y = 4
D. 5 w + 6 w - 3w = 64, w = 8
E. t - 2t - 3t = 32, t = 8

I'll show you the steps and you can find the answer
A. 2x + 5 (x-1) = 9, x = 2
multiply 5 times (x-1) then reduce the terms
2x + 5x - 5 = 9
7x - 5 = 9
(add 5 to both sides of the equation)
7x - 5 + 5 = 9 + 5
7x = 14
7x / 7 = 14 / 7 ; (divided both sides by 7)
x = 2

B. p - 3(p-5) = 10, p = 2.5
p - 3p + 15 = 10 ; (multiplied -3 times p, and -3 times -5
-2p + 15 = 10 ( p -3p = -2p)
-2p + 15 + 2p = 10 + 2p ; (add 2p to both sides - it's easier them the variable is a positive)
15 = 10 + 2p
15 - 10 = 10 - 10 + 2p ; (subtract 10 from both sides)
5 = 2p
5 / 2 = 2p / 2 ; (divide both sides by 2)
2.5 = p

C. 4 y + 3 y = 28, y = 4
7y = 28 ; (4y + 3y = 7y; you can also express this as 4y + 3y = y(4+3) = 7y)
7y / 7 = 28 / 7 ; (divide boith sode by 7)
y = 4

D. 5 w + 6 w - 3w = 64, w = 8
8w = 64 ; ( 5w + 6w - 3w = 8w)
8w / 8 = 64 / 8 ; (divide both sides by 8)
w = 8

E. t - 2t - 3t = 32, t = 8
-4t = 32 (1t - 2t - 3t = -4t)
-4t / 4 = 32 / 4 ; (divide both sides by 4)
-t = 8
-t * -1 = 8 * -1 (multiply both sides by negative 1)
t = -8

Well, for A, since x=2, 2*2=4 and then 4+5=9 then 2-1 is 1 and 9*1 is 9 só 9=9

E.

If t = 8, then t - 2t - 3t = -4t = -4(8) = -32.
And -32 is not equal to 32.

That last one just isn't my cup of tea!