A is directly proportional to the square root of B
When A = 50, B+4 . Find A in terms of B

A=50, B=4

A is directly proportional to the square root of B

name the constant 'k'

A = k*B^0.5

50 = k*4^0.5

50=2k

k=25

=> A =25 root B

i.e, A = 25*B^0.5 (The answer should be written the way it is written in the attached picture)

it would be 6xy and -16xy.

the answer to the expression is 83