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


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 , m=slope, and (0,b) is the y-intercept.

Happy Calculating!!!
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