How do i find the length of
——
ab

As you know, in a parallelogram the opposite side are equal

So,

AB = DC

6x - 8 = 3x + 4

6x - 3x = 8 + 4

3x = 12

x = 12 / 3

x = 4

Therefore,

6x-8

= 6(4) - 8

= 24 - 8

= 16 units

let m = monomial

let t = trinomial

so, m times t = t.

monomial times a trinomial = another trinomial.