Hi sorry for the messy writing ignore everything else written in pencil
Option #1 (and the fastest):
Multiply both sides by 3 to cancel the “divided by 3” on the left side where z is.
z/3 • 3 = 5/4 •3
z = 15/4
Option #2: Cross multiply and then solve for z:
z/3 = 5/4 -> 4z=15
Then divide by 4.
4z/4 = 15/4
z = 15/4

Do the multiplication both sides,

Arrange the terms to LHS according to their variables,

Factorise this polynomial

So what we notice here is when you're multiplying two numbers you're getting 0 as answer.
So one of them must be 0.
If (x-1) is 0
then x = 1
similarly,
x-6=0
then, x= 6.
So the possible values of x are 1 and 6.
It C)
This is because the sum of the two smaller sides in a triangle has to be larger than the bigger sides. 10+12=22.
22 is smaller than 24 which is the third side this no triangle is formed