SOLUTION: Hi! Can I have some help finding an equation of the line through (7, 8) and parallel to the line 4x - y = 5?

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Question 124622: Hi! Can I have some help finding an equation of the line through (7, 8) and parallel to the line 4x - y = 5?

Answer by iluvbuilding429(41) About Me  (Show Source):
You can put this solution on YOUR website!
Hi! Can I have some help finding an equation of the line through (7, 8) and parallel to the line 4x - y = 5?


To better understand this problem, put the equation in slope-intercept form:
y=4x-5
This shows you that the slope is 4, and the y-intercept is 5. Since parallel lines always have the same slope, you know that the line that runs through (7,8) will have a slope of 4.
y=4x%2Bb
All you need to know now is the y-intercept.


To find it, plug in (7,8) for x and y.
8=4%287%29%2Bb


Multiply:
8=28%2Bb


Subtract 28 from both sides:
-20=b
Now you know the y-intercept. Plug this value into your equation to get your answer.
y=4x-20


To check, add in the values from the coordinate:
8=4%287%29-20


Multiply:
8=28-20


Subtract:
8=8