The closest one is 5 to the power of 1 over 3.
sq rt of 3 = 1.732
sq rt of 5 = 2.236
5^1/3 = 1.667
5^1/6 = 0.833
5^2/3 = 8.333
5^3/2 = 62.5
A = 8B
A + B = 180
8B + B = 180
9B = 180
B = 20
A = 8 * 20 = 160
The answer is -6.825 in fraction form, it would be -6 33/40
Multiply everything by 2 then combine like terms