After esayas's birthday party, 3/4 of a pizza remained. esayas wants to share the pizza with 5 of his friends. what part of the pizza will esayas and each of his friends recieve?

Esaya wants to DIVIDE the remaining 3/4 into 6 pieces ...
(one piece for himself and each friend).

So each person will get      3/4 ÷ 6    of a pizza.

To divide, you invert the divisor and then multiply:

                                           3/4 · 1/6  =  3/24 or 1/8 of a pizza.

The answer is a + 12

Solution:
In order to solve it, you need to separately solve the numbers that have something in common- for ex: if they are just numbers, or if they have the same exact variables

In order to make it easier, you can rearrange the equation
4a - 3a + 19 - 7
4a - 3a = a
19 - 7 = 12

Since these numbers can't be combined due to the fact that they have nothing in common, you leave the equation as is, resulting in the

a + 12