SOLUTION: write an equation that describes the line that passes through [-3,1] and is parallel to the line described by y= 4x + 1 ?

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Question 568540: write an equation that describes the line that passes through [-3,1] and is parallel to the line described by y= 4x + 1 ?
Found 2 solutions by Tatiana_Stebko, nyc_function:
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
If line is parallel to the given line y=+4x+%2B+1, then it has an equation y=+4x+%2B+b
(Parallel lines have equal slopes)
To find b substitute into the equation x=-3, y=1
1=4%2A%28-3%29%2Bb
1=-12%2Bb
b=1%2B12
b=13
Answer y=4x%2B13

Answer by nyc_function(2741) About Me  (Show Source):
You can put this solution on YOUR website!
The line we want will need to have the same slope as the given line.

The slope of the given line is the coefficient of x.

What is the slope?

The slope is 4. Do you see it in your equation?

We now use the point-slope formula y - y1 = m(x - x1).

NOTE: y1 is read "y sub 1" and x1 is read "x sub one".

We plug the given point and slope into the formula to find a line parallel to the given line.

Let y1 = 1

Let x1 = -3

Let m = slope = 4

We now plug and chug.

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

y - 1 = 4(x + 3)

y - 1 = 4x + 12

y = 4x + 12 + 1

y = 4x + 13

Did you follow?