Question

(a-1)a-a(a+1) = 50 

Answer 1

`-> a^2 - a - a^2 - a = 50`

`=> -2a = 50`

`=> a = -25`.

Answer 2

<=> \(a^2-a-a^2-a=50\)

<=> -2a = 50

=> a= 50 : -2 = -25

Answer 3

<=> a^2-a-a^2-a=50

<=>-2a=50

=> a=50/(-2)=-25

Answer 4

(a-1-a-1)a=50
-2a=50
a=-25