A line passes through the point (–2, 4), and its y-intercept is (0, –6). What is the equation of the line that is perpendicular to the first line and passes through the point (5, –4)?
a. y=1/3x-3
b. y=5x-3
c.y=1/5x-5
y=5/3x-2

Respuesta :

y= mx +b
the first line:
sustitute:
4=m(-2)+b
remplace intercept in y:
4=-2m-6
-2m=(4+6)/-2
m=-5
The first equation is y=-5x-6
For the perpendicular the slope is 1/5
so
y-y1=m(x-x1)   use the second coordenates
y+4= 1/5(x-5)
y=(1/5)x-1-4
y=(1/5)x-5  That's the answer: Letter C
little late for me now but for future reference those equations are y=mx+b form X is rise/run and B if you go up or down, then its just a matter of graphing your lines to determine the point of intersection. you might've gotten youre answer, maybe not but now you can find it in less time