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Can anyone help me with these 4 questions i havw no idea what to do

Can anyone help me with these 4 questions i havw no idea what to do-example-1
User Barclay
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1 Answer

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Consider the problem 15. We have the point (5,-4) and the line y=(1/5)x-4 and we want the equation of a line that passes through the given point that is parallel to the given line. Recall that the general equation of a line is of the form y=mx+b where m is the slope and b is the y intercept. Also, have in mind that two lines are parallel if and only if they have the same slope. Let us have the equation we are looking for as y=mx+b. Since this line must be parallel to the line y=(1/5)x-4 it must happen that they have the same slope. For the line y=(1/5)x-4 the slope is (1/5). Then the slope of the line we are looking for is also (1/5).

Now, we should determine the value of b. So far we have this expression


y=(1)/(5)\cdot x+b

We want this line to pass through the point (5,-4). So, this means that whenever we replace x by 5, we should also replace y by -4. This gives us the equation


-4=(1)/(5)\cdot5+b

which is the equation


b+1=-4

by subtracting 1 on both sides, we get


b=-4-1=-5

So the equation of our line would be


y=(1)/(5)x-5

User Thomas Manalil
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