Given the function f(x)=5(x+4)^3/2, which of the following represents its y-intercept? (1)40 (2)20 (3)4 (4)30

f(x)=5(x+4)^3/2,    let y = f(x).

y =5(x+4)^3/2.  The y intercept is value of y when x = 0

y intercept =  5(0+4)^3/2 =  5*  4^3.2 =  5*6 = 30.      Use your calculator.
 
y intercept  = 30

Ithink the answer would be knew