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Write the equation of a line that is parallel to y = 3x and goes through (-2, 1).

User Toribio
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1 Answer

7 votes

Answer:

y = 3x + 7

Explanation:

If two lines are parallel to each other, they have the same slope.

The first line is y = 3x. Its slope is 3. A line parallel to this one will also have a slope of 3.

Plug this value (3) into your standard point-slope equation of y = mx + b.

y = 3x + b

To find b, we want to plug in a value that we know is on this line: in this case, it is (-2, 1). Plug in the x and y values into the x and y of the standard equation.

1 = 3(-2) + b

To find b, multiply the slope and the input of x (-2)

1 = -6 + b

Now, add 6 to both sides to isolate b.

7 = b

Plug this into your standard equation.

y = 3x + 7

This equation is parallel to your given equation (y = 3x) and contains point (-2, 1)

Hope this helps!

User Ollo
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