Please explain how to solve:

Question

Reid and Maria both play soccer. This season, Reid scored 4 less than twice the number of goals that Maria scored. The difference in the number of goals they scored was 6. How many goals did each of them score?

Answer 1

You have to learn to "translate" the English into Math

In this case there are two unknowns, the number of goals scored by Maria and the number of goals scored by Reid.
You are told a relationship between them
I usually define the smaller quantity, in this case the number of goals scored by Maria
Let the number of goals scored by Maria be x
We are told: "Reid scored 4 less than twice the number of goals that Maria scored"

".. twice the number of goals that Maria scored" --- > 2x
" 4 less than ...." --->2x - 4

So now we have Maria scoring x goals and
Reid scoring 2x-4 goals

"The difference in the number of goals they scored was 6" translated ...
(2x-4) - (x) = 6
2x-4-x = 6
x = 10

so Maria scored 10
Reid scored 2(10)-4 or 16

See how easy it is?