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PLEASE HELP ASAP!

A line is drawn so that it passes through the points (-3,-1) and (4,2).

a. What is the slope of the line?

b. Using the point (4,2) and the slope found above, write the equation of the line in point-slope form.

Please write out how you got your answer or the steps you took.

1 Answer

5 votes
A) To find slope, use the equation:
slope = ( y_(2) - y_(1) )/(x_(2)-x_(1))where
x_(2) and
y_(2) are the x and y values of one coordinate point , and
x_(1) and
y_(1) are the x and y values of another coordinate point . Since we are given two coordinate points, (-3,-1) and (4,2), that means we can find the slope using the slope equation.
Let's choose (4, 2) as your
(x_(2), y_(2)) point and (-3, -1) as your
(x_(1), y_(1)) point, but you can switch those if you want! That makes
x_(2) = 4, y_(2) = 2 and
x_(1) = -3, y_(1) = -1. Plug these values into the slope equation:

slope = ( y_(2) - y_(1) )/(x_(2)-x_(1)) \\ slope = (2-(-1))/(4-(-3)) \\ slope = (3)/(7)

The slope of the line is 3/7.

B) Remember that the general equation for point-slope form is
y - y_1 = m(x - x_1), where m = the slope,
x_(1) = the x value of a coordinate point
(x_(1), y_(2)) on the line, and
y_(1) = the y value of the same coordinate point on the line.

You are given (4, 2) as one of the coordinate points. That means
x_(1) = 4 and
y_(1) = 2. We found the slope, m =
(3)/(7) in part A. Now plug these values into the general equation for point-slope form to find your point-slope form equation:

y - y_1 = m(x - x_1)\\ y - 2 = (3)/(7)(x - 4)

Your point-slope form equation is
y - 2 = (3)/(7)(x - 4).


User JafarKhQ
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