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Write an equation of the line that passes through (4,−1) and is parallel to the line y=3x+7. (hint: NOT y=3x-13)

User Colwin
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1 Answer

3 votes

To find the equation of the line, we are going to use the point-slope form, which is listed below:


(y - y_1) = m(x - x_1)


  • (x_1, y_1) is a point on the line

  • m is the slope of the line

You may notice that we have a point, but no slope is given to us. However, the problem states that the line is parallel to the equation
y = 3x + 7, which means that it has the same slope as this line, which is 3. (Remember that this line is set up in
y = mx + b form, where
m is the slope)


Thus, we can now insert our values into the point-slope formula to find the equation of our line.


(y + 1) = 3(x - 4)


(y + 1) = 3x - 12


y = 3x - 13


The problem made it clear that it didn't want the form
y = 3x - 13, so let's put it in standard form:


y = 3x - 13


3x - y = 13


The equation of our line is
\boxed{3x - y = 13}.

User Benoir
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