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How to find the value of "k"in completing a table of direct variation if u don't have the first entry for "Y"?

Find "k" and complete the table when y=kx
X...| 2 | 4 | --| 7 |
Y...|-- |28|42|--|

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Philip P. | Effective and Affordable Math TutorEffective and Affordable Math Tutor
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y = kx,  so y/x = k
You have two values of y and x from the table, (4,28).  Hence:
k = y/x = 28/4 = 7
So the equation is y = 7x.
Now we can complete the table.  For the entry x=2, we can compute y= 7x = 7*2 = 14, so put a 14 below the 2 in the table.  You should be able to complete the rest of the table on your own now.


Sammad, this must have been the table you were referring to in your other comment. As Philip showed you, there is an entry with both X and Y so that you can solve for k.  I'm sure you can finish from what he gave you!