SOLUTION: PLEASE help me solve this. Y varies jointly as j and B^2. when j=3 and B=6, y=216. Find y when j is 9 and b is 10. y= ?

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: PLEASE help me solve this. Y varies jointly as j and B^2. when j=3 and B=6, y=216. Find y when j is 9 and b is 10. y= ?       Log On


   

Question 821262: PLEASE help me solve this.
Y varies jointly as j and B^2. when j=3 and B=6, y=216. Find y when j is 9 and b is 10.
y= ?
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
Y = k *j *B^2 where j=3, B=6, y=216 note that k is the constant of proportionality, therefore
216 = k *3 *6^2
216 = k*108
k = 216/108 = 2
now we can solve for y when j=9 and b=10
y = 2*9*10^2
y = 18 * 100 = 1800