*l*contains points (0,0) and (

*t*,

*t*+1).

Since we also know that it's perpendicular to the line

*y*= -4

*x*+

*k*, we know line

*l*has a slope of +1/4 (the negative reciprocal of the slope of the line it's perpendicular to).

We can use these two facts to solve for

*t*. Set up the slope equation using the points we know:

1/4 = [

*t*+ 1 -0]/[*t*- 0]1/4 = [

*t*+ 1]/[*t*]*t*/4 =

*t*+ 1

*t*= 4

*t*+ 4

-3

*t*= 4*t*= -4/3

Hi, sorry i'm about to ask a dumb question. in the original sat, the other line was 4x+y=k so why did it change to -4x+k

ReplyDeleteThat's just converting the original equation to y = mx + b form

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