Write the equation of a line in slope-intercept form that goes through the points (4, -2) and (-4, -4). A. y = 1/4x - 3 B. y = 4x - 3 C. y = 4x - 2 d y = 1/4x - 2
Mathematics · College · Thu Feb 04 2021
Answered on
Given the points:
(4, -2)
(-4, -4)
x1= 4
x2 = -4
y1 = 2
y2= -4
Write the equation in slope-intercept form.
Before writing in slope-intercept form, we must first write in point-slope form
Point-slope form:
y - y1 =m(x -x1)
Slope-intercept form:
y = mx + b
Solution:
Before we can write in point-slope form, we must first find the slope of the line, we can find the slope by using the slope formula.
m = y2 -y1 /x2 -x1
m= (-4 -2)/(-4 - 4)
m = -2/-8
m= ¼
Substitute the given values of x1, y1 and m to the formula for the point-slope form.
y - 2 = ¼ ( x - 4 )
In order to equate to slope-intercept form, we simply need to distribute ¼ to the parenthesis, then transpose -2 to the other side of the equation. Hence we must take note that in transposing a number, the sign changes.
y - 2 = ¼x - 1
y = ¼x - 1 + 2
y = ¼x + 1
Final answer:
y = ¼x + 1