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Write the equation of the line parallel to 4x - 5y=12 and passing through the point (5, 7).

User Geemus
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1 Answer

21 votes
21 votes

Answer:

y = (4/5)x + 3

Step-by-step explanation:

First, we need to identify the slope of 4x - 5y = 12. To identify the slope we need to solve the equation for y as:


\begin{gathered} 4x-5y=12 \\ -5y=12-4x \\ y=(12-4x)/(-5) \\ y=(-12)/(5)+(4)/(5)x \end{gathered}

Since 4/5 is the number beside the x, 4/5 is the slope of the line.

Now, two lines are parallel if they have the same slope, so the slope of our equation will be 4/5.

Then, the equation of a line with slope m that passes through the point (x1, y1) is:


y-y_1=m(x-x_1)

So, replacing m by 4/5 and (x1, y1) by (5, 7), we get:


y-7=(4)/(5)(x-5)

Finally, solving for y, we get:


\begin{gathered} y-7=(4)/(5)x-(4)/(5)\cdot5 \\ y-7=(4)/(5)x-4 \\ y=(4)/(5)x-4+7 \\ y=(4)/(5)x+3 \end{gathered}

Therefore, the equation of the line is:

y = (4/5)x + 3

User Stefano L
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