Given the square of a + the square of B = 25, ab = 12, find a + B

Given the square of a + the square of B = 25, ab = 12, find a + B

a^2+b^2=25
ab=12
So (a + b) ^ 2 = a ^ 2 + B ^ 2 + 2 * AB = 25 + 2 * 12 = 49
So a + B = plus or minus 7