Write the equation of the line that passes through (-9,-4) and (-6,-2) in slope-intercept form.(Fraction not division)
a. y= (3/2x) +7b. y=−(2/3x)−6c. y=(2/3x)−6d. y=(2/3x)+2

Respuesta :

DeanR

In general the line through (a,b) and (c,d) is


[tex](c-a)(y-b)=(d-b)(x-a)[/tex]


Can you see why?


Here we have


[tex](-6 - -9)(y - -4) = (-2 - - 4)(x- -9)[/tex]


[tex]3(y+4)= 2(x+9)[/tex]


[tex]3y + 12 = 2x + 18[/tex]


[tex]3y = 2x + 6[/tex]


[tex] y = \frac 2 3 x + 2[/tex]


That's choice d, though I would parenthesize it as y=(2/3)x+2 so it doesn't look like we're dividing by x.