4. Find the value of YZ

They are parallel so that means that they are congruent (equal)
19x-31=11x+1
So now you solve like a normal equation

Let’s move things around, variables to the left, non variables to the right (remember that when moving to different sides they become opposites, [adding becomes subtraction, subtraction becomes addition])

19x-11x=31+1

Now add/subtract like terms
19x-11x=8x
31+1=32

New equation 8x=32

Now you divide 32/8 which would be 4

The value of x is 4

So now to get the value of YZ you plug in the value of X where you see an X

Instead of 19x-31 it’d be 19(4)-31

Now you solve that And get 45

45

The answer is something i don’t know