Find the Value of k

**magentarita** · October 14th 2008, 08:58 PM

If point (k,3k) lies on the graph of the equation
3x + y = 12, what is the value of k?

**mr fantastic** · October 14th 2008, 09:00 PM

Originally Posted by magentarita

If point (k,3k) lies on the graph of the equation
3x + y = 12, what is the value of k?

Solve 3(k) + (3k) = 12 for k.

**magentarita** · October 16th 2008, 06:13 PM

Originally Posted by mr fantastic

Solve 3(k) + (3k) = 12 for k.

How did you know what equation to use?

**mr fantastic** · October 16th 2008, 09:29 PM

Originally Posted by magentarita

How did you know what equation to use?

They give it to you!

(k,3k) lies on the graph of the equation
3x + y = 12,

Substitute x = k and y = 3k into 3x + y = 12.

**magentarita** · October 17th 2008, 02:31 AM

Originally Posted by mr fantastic

They give it to you!

Substitute x = k and y = 3k into 3x + y = 12.

The point written as it is through me off a bit.

Thanks

Thread: Find the Value of k