SOLUTION: WRITE AN EQUATION FOR EACH LINE with a slope of 2 and a y-intercept of 4 through (0,-4) and with a slope of 1.5 please help!!

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Question 100457: WRITE AN EQUATION FOR EACH LINE
with a slope of 2 and a y-intercept of 4
through (0,-4) and with a slope of 1.5
please help!!

Found 2 solutions by jim_thompson5910, checkley71:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
"WRITE AN EQUATION FOR EACH LINE
with a slope of 2 and a y-intercept of 4"



When you have a y-intercept of 4, that means the point (0,4) is on the line



If you want to find the equation of line with a given a slope of 2 which goes through the point (0,4), you can simply use the point-slope formula to find the equation:


---Point-Slope Formula---
y-y%5B1%5D=m%28x-x%5B1%5D%29 where m is the slope, and is the given point

So lets use the Point-Slope Formula to find the equation of the line

y-4=%282%29%28x-0%29 Plug in m=2, x%5B1%5D=0, and y%5B1%5D=4 (these values are given)


y-4=2x%2B%282%29%28-0%29 Distribute 2

y-4=2x%2B0 Multiply 2 and -0 to get 0

y=2x%2B0%2B4 Add 4 to both sides to isolate y

y=2x%2B4 Combine like terms 0 and 4 to get 4
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Answer:


So the equation of the line with a slope of 2 which goes through the point (0,4) is:

y=2x%2B4 which is now in y=mx%2Bb form where the slope is m=2 and the y-intercept is b=4

Notice if we graph the equation y=2x%2B4 and plot the point (0,4), we get (note: if you need help with graphing, check out this solver)

Graph of y=2x%2B4 through the point (0,4)
and we can see that the point lies on the line. Since we know the equation has a slope of 2 and goes through the point (0,4), this verifies our answer.





"WRITE AN EQUATION FOR EACH LINE
through (0,-4) and with a slope of 1.5"


when you have a slope of 1.5, you really have a slope of 3%2F2




If you want to find the equation of line with a given a slope of 3%2F2 which goes through the point (0,-4), you can simply use the point-slope formula to find the equation:


---Point-Slope Formula---
y-y%5B1%5D=m%28x-x%5B1%5D%29 where m is the slope, and is the given point

So lets use the Point-Slope Formula to find the equation of the line

y--4=%283%2F2%29%28x-0%29 Plug in m=3%2F2, x%5B1%5D=0, and y%5B1%5D=-4 (these values are given)


y%2B4=%283%2F2%29%28x-0%29 Rewrite y--4 as y%2B4


y%2B4=%283%2F2%29x%2B%283%2F2%29%28-0%29 Distribute 3%2F2

y%2B4=%283%2F2%29x%2B0 Multiply 3%2F2 and -0 to get 0

y=%283%2F2%29x%2B0-4 Subtract 4 from both sides to isolate y

y=%283%2F2%29x-4 Combine like terms 0 and -4 to get -4
------------------------------------------------------------------------------------------------------------
Answer:


So the equation of the line with a slope of 3%2F2 which goes through the point (0,-4) is:

y=%283%2F2%29x-4 which is now in y=mx%2Bb form where the slope is m=3%2F2 and the y-intercept is b=-4

Notice if we graph the equation y=%283%2F2%29x-4 and plot the point (0,-4), we get (note: if you need help with graphing, check out this
solver)

Graph of y=%283%2F2%29x-4 through the point (0,-4)
and we can see that the point lies on the line. Since we know the equation has a slope of 3%2F2 and goes through the point (0,-4), this verifies our answer.

Answer by
checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
Y=mX+b IS THE LINE EQUATION.
Y=2X+4 THIS EQUATION HAS A SLOPE (m) OF 2 & A Y INTERCEPT (b) OF 4.
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-4=-1.5*0+b
b=-4 FOR THE Y INTERCEPT.
Y=-1.5X-4 ANSWER.