Question

NEED HELP ASAP!!PLZ????!!!!!!!
Variable y varies directly with x2, and y = 72 when x = 6.

What is the value of y when x = 4?

y = ? x^2

Answer 1

o.O

Answer 2

Im kinda in a hurry............

Answer 3

Right, then let's make this quick.

Can I assume you know what "varies directly" means?

Answer 4

Not really :/

Answer 5

Okay, two things vary directly if one of them if their QUOTIENT is always the same.

So here, y varies directly with x^2.

That means
\[\Large \frac{x^2}{y}\] will ALWAYS be the same, no matter what values x and y take...

Answer 6

Ok

Answer 7

Now, we know it's always the same, we just need to know what IT is.

You're given that if y is 72 then x is 6.

Let's try plugging that in:
\[\Large \frac{6^2}{72}\]
What is this equal to?

Answer 8

Common denominator is 12....
Simplify to : 1 whole?
\[\frac{ 12 }{ 72 } \]

Answer 9

Whoa... back up there :D
\[\Large 6^2 \color{red}\ne 2\times 6\\\Large 6^2 = 6\times6\]

Answer 10

Sorry my internet went out

Answer 11

I did it wrong ???? @supreme_kurt

Answer 12

I lost my connection too. I'm so sorry. :(