for a number to be a solution to an equation, it has to satisfy the equation...it has to make the equation true.
for example :
2n + 6 = 10.....n is our unknown number
2n = 10 - 6
2n = 4
n = 4/2
n = 2...so the number that makes the equation true is 2
and to check if the number is a solution, we then sub that number back into the original equation to see if it makes the equation true.
2n + 6 = 10
2(2) + 6 = 10
4 + 6 = 10
10 = 10 (correct)
so our number (n) represents the number 2, and it does make the equation true
