SOLUTION: I do not understand this question - please help me Find the slope of the line through the given points. Also find the slope intercept form. Find the Y intercept and the X inte

Question 103056This question is from textbook
: I do not understand this question - please help me
Find the slope of the line through the given points. Also find the slope intercept form. Find the Y intercept and the X intercept for one of the points.
(-7/5, 3/10) and 1/5, -1/2) This question is from textbook

Answer by oberobic(2304) (Show Source): You can put this solution on YOUR website!
The two points are (-7/5, 3/10) and (1/5, -1/2).
The slope is the rise / run = change in y divided by the change in x.
Change in y = -1/2 - 3/10 = -5/10 - 3/10 = -8/10 = -4/5.
Change in x = 1/5 - (-7/5) = 1/5 + 7/5 = 8/5.
So the slope is

Dividing by fractions can be handled by multiplying using the reciprocal, so:

The 5's cancel each other, so you have slope = -4/8 = -1/2.
By convention, we call that m. It fits into the standard equation for a line, which you may recall is y = mx + b.
So, we now know that y = -1/2x + b.
But what is b?
That is the place the line crosses the y-axis when when x=0, or the y-intercept. But that is just a definition, not an answer.
Hmmm....
Well, we know one of the points is (1/5, -1/2), so that is a valid (x,y) pair.
Substituting what we know into y = mx + b, we have:
-1/2 = -1/2*1/5 + b
Multiplying:
-1/2 = -1/10 + b
Now add 1/10 to both sides:
-1/2 + 1/10 = b
-5/10 + 1/10 = b
-4/10 = b = -2/5
Aha!
y = -1/2x - 2/5.
Looking back at the question, it also calls for us to find the x-intercept. That is the place it crosses the x-axis when y=0.
So, substituting y=0:
0 = -1/2x - 2/5
Adding 2/5 to both sides:
2/5 = -1/2x
Multiplying by 2 to eliminate the fractional coefficient of x:
4/5 = -x
Multiplying by -1 to get x to be positive:
x = -4/5.
So, the x-intercept is at x=-4/5 (that is, the pair (-4/5,0).
RELATED QUESTIONS
Find the slope of the line passing through the points (-9,-4) (0,-4) Please help I... (answered by checkley71)

Find the slope, if it exists of the line containing the pair of points (2, 5) and (3,... (answered by Earlsdon)

Find the slope of the line that goes through the given points. (-1, 4), (5, 4)... (answered by rfer)

what would the slope of the line be through the two points (-4,-2) and (-1,-1) I do not... (answered by Earlsdon)

Graph the line containing the given pair of points and find the slope. (4,0), (-2, -3) (answered by rapaljer)

Please help me find the slope of the line that goes through the given points (6,6) and... (answered by doukungfoo)

Find the slope of the line that goes through the given points. (-4,2), (-3,2) Please... (answered by ewatrrr)

help me find the slope of the line that passes through these given points (1,7)... (answered by rfer)