SOLUTION: y varies directly with x and has a constant rate of change of 7. When the value of y is 12, then the value of x would be?

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Question 388262: y varies directly with x and has a constant rate of change of 7.
When the value of y is 12, then the value of x would be?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

A change in one quantity with respect to another quantity is called a
rate+of+change .
Any rate of change can be described in terms of slope, or change_in_y%2Fchange_in_x.
A special type of equation that describes a rate of change is a
linear equation in the form of y+=kx, where k is not equal to 0, and is called direct variation.
In direct variation we say that y varies directly with x or y varies directly as x.
In the direct variation equation, y+=kx, k is the
constant of variation.
The constant of variation in a direct variation equation has the same+value as the slope of the graph.
For example:
y+=3x is a direct variation because it is in the form of y+=kx.
The constant of variation of y+=3x is 3.
The slope of the linear graph of y=3x is 3. All direct variation graphs pass through the origin.

So, in your case we have:y+=7x. The constant of variation it is 7.
If the value of y is 12, then the value of x would be x=y%2F7 or x=12%2F7.
x=1.7