If point (k,3k) lies on the graph of the equation 3x + y = 12, what is the value of k?
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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.
Originally Posted by mr fantastic Solve 3(k) + (3k) = 12 for k. How did you know what equation to use?
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.
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