Question

PLEASE HELP GIVING MEDAL
Which is the quadratic variation equation for the relationship?

y varies directly with x2 and y = 72 when x = 6.


A.
y = 4x^2

B.
y = 2x^2

C.
y = x^2 + 25

D.
y = 12x

Answer 1

@dire

Answer 2

@Directrix

Answer 3

do you know the formula for direct variation ??

Answer 4

cananyone help please?

Answer 5

not really

Answer 6

sorry

Answer 7

y varies directly with x2"
means y = k x^2 (where k is the number you want to find)

they gave you x and y, plug in
so 72 = k (6^2) and solve for k

Answer 8

\[\huge\rm y =kx \]formula for direct variation
but u need equation for quadratic variation so x suppose to be square \[\huge\rm y = kx^2\] now just substitute x and y values

Answer 9

72x6?

Answer 10

nope first take square of 6

Answer 11

36?

Answer 12

look at link http://openstudy.com/study#/updates/53054dade4b022471a64d160

Answer 13

yep so now you have \[\huge\rm 72 = 36k\]
solve for k
there is 36 times k so you have to do opposite of multiply to cancel out 36 from right side

Answer 14

0?

Answer 15

@Nnesha

Answer 16

Does the link help? @ACU17

Answer 17

not really

Answer 18

nope divide both side by 36

Answer 19

yep right side 36/36 cancel out what about other side you need to divide
"both side" by 36

Answer 20

are you kidding?? that is clear as day