PLEASE HELP AND EXPLAIN HOW TO DO IT
For the above graph determine
a. the slope m
b. the y-intercept b
c. write the equation of the line in slope-intercept form
d. use your equation to find the x-intercept.

PLEASE HELP AND EXPLAIN HOW TO DO IT For the above graph determine a the slope m b the yintercept b c write the equation of the line in slopeintercept form d us class=

Respuesta :

(0,-2)(- 2,1)....I found 2 whole number sets of points
slope = (y2 - y1) / (x2 - x1)
(0,-2)....x1 = 0 and y1 = -2
(-2,1)...x2 = -2 and y2 = 1
now we sub
slope = (1 - (-2) / (-2 - 0) = (1 + 2) / -2 = -3/2...this is ur slope

the y intercept is where the line cross the y axis...and it is -2 or (0,-2)...this is one way to find it....there is another way that I will show u later in the problem

y = mx + b
slope(m) = -3/2
u can use either of ur points (-2,1)...x = -2 and y = 1
now sub and find b, the y intercept
1 = -3/2(-2) + b
1 = 3 + b
1 - 3 = b
-2 = b .......this is the other way to find the y int.

so ur equation is : y = -3/2x - 2.....and in y = mx + b form, the slope is in the m position and the y int is in the b position

to find the x intercept, take ur equation, sub in 0 for y and solve for x...or u could look at ur graph and see where the line crosses the x axis...but in this problem that would not be easy because it is not a whole number
y = -3/2x - 2
0 = -3/2x - 2
3/2x = -2
x = -2 / (3/2)
x = -2 * 2/3
x = -4/3 or (-4/3,0)

u could also find the y int by subbing in 0 for x and solving for y