Solve the equation for the indicated variable :

Y = 3/8(x + 4)multiply both sides by 8/3, eliminating the 3/8 o the right
8/3y = x + 4now subtract 4 from both sides
8/3y - 4 = x <==

n = m^2 - (n + 3)
n = m^2 -n - 3...add n to both sides
n + n = m^2 - 3
2n = m^2 - 3...add 3 to both sides
2n + 3 = m^2...take sqrt of both sides, eliminating the ^2
sqrt (2n + 3) = m or m = - sqrt (2n + 3) <==