SOLUTION: A line passes through (-4,2) and has the same y-intercept as 2x-y=3. Put this in standard form.

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Question 59576This question is from textbook The Learning Equation
: A line passes through (-4,2) and has the same y-intercept as 2x-y=3. Put this in standard form. This question is from textbook The Learning Equation

Found 2 solutions by Edwin McCravy, funmath:
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
A line passes through (-4,2) and has the same y-intercept as 2x-y=3.
Put this in standard form.

First we get 2x - y = 3 into slope-y-intercept form y = mx + b
by solving it for y

       2x - y = 3

Add -2x to both sides

           -y = 3 - 2x

Divide through by -1

            y = -3 + 2x

Reverse the order of the terms on the right

            y = 2x - 3

Now we can compare that to

            y = mx + b

and see that its slope is m = 2 and its
y-intercept is b = -3. We don't need its
slope but we do need its y-intercept b = -3

This means the the line that we are looking for
also crosses the y-axis at the point (0, -3).  
That means the problem is now this one:

Find the equation of the line that passes
through the two points (-4, 2) and (0, -3).
We use the slope formula:

     y2 - y1
m = --------- 
     x2 - x1
           
where (x1, y1) = (-4, 2) 
and (x2, y2) = (0, -3)

     (-3) - (2)     -5
m = ------------ = ----- = -5/4 
     (0) - (-4)      4

Then we can either use the point-slope
formula 

y - y1 = m(x - x1)

or the slope-y-intercept

y = mx + b

either way we end up with 

y = -5/4x - 3

To put this in standard form, we

1. Clear of fractions

2. Get the x term first, the y term
   second, the equal sign third, and
   the constant term fourth.

3.  If the x term has a negative
    coefficient, multiply through by 
    -1 to make it positive.

y = -5/4x - 3

Multiply through by 4

4y = -5x - 12

Add 5x to both sides

5x + 4y = -12

Edwin

Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
A line passes through (-4,2) and has the same y-intercept as 2x-y=3. Put this in standard form.
This is a thinker.
To find the y-intercept of the equation of a line you can let x=0 and solve for y.
2(0)-y=3
0-y=3
-y=3
-(y)=-(3)
y=-3 The y-intercept is (0,-3)
To find an equation of a line we need a slope and a point. We don't have a slope, but we do have two points. We can find the slope between two points with the slope formula: highlight%28m=%28y2-y1%29%2F%28x2-x1%29%29
(x1,y1)=(-4,2) and (x2,y2)=(0,-3)
m=%28-3-2%29%2F%280-%28-4%29%29
m=-5%2F4
Now we can use the slope, m=-5/4 and the y-intercept (0,b)=(0,-3) To make an equation of a line with the slope intercep formula highlight%28y=mx%2Bb%29, m=slope, and (0,b) is the y-intercept.
highlight%28y=%28-5%2F4%29x-3%29
Happy Calculating!!!