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2) Find the equation of a line that is parallel to y = 5x + 7 and passes through (4, 3)

User Lee Berger
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1 Answer

21 votes
21 votes

Answer:

y=5x-17

Explanation:

Given the equation of the line: y=5x+7.

We want to find a line parallel to it that passes through (4,3).

Slopes are used to determine if two lines are parallel or not.

First, we determine the slope of y=5x+7 with the slope-intercept form of a line.


\begin{gathered} y=mx+b \\ y=5x+7 \\ \implies\text{Slope,m = 5} \end{gathered}

Two lines are parallel if they have the same slope.

• Therefore, the slope of the new line = 5

Since the two lines are parallel, the new line has the following properties:

• Slope, m =5

,

• Point, (x1,y1)=(4,3)

We then use these to find the required equation of the line.

Substitute the slope and point into the point-slope form of a line.


\begin{gathered} y-y_1=m(x-x_1) \\ \implies y-3=5(x-4) \end{gathered}

We then rewrite it in the slope-intercept form.


\begin{gathered} \text{Open the bracket} \\ y-3=5x-20 \\ Add\text{ 3 to both sides} \\ y-3+3=5x-20+3 \\ y=5x-17 \end{gathered}

The required equation of the line is y=5x-17.

User Jankal
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3.1k points