Question

Tabitha is trying to find the equation of a line perpendicular to y = 1 over 2x − 5 in slope-intercept form that passes through the point (2, −7). Which of the following equations will she use?

Answer 1

a) y − (−7) = 1 over 2(x − 2)
b) y − 2 = 1 over 2(x − (−7))
c) y − (−7) = −2(x − 2)
d) y − 2 = −2(x − (−7))

Answer 2

@satellite73

Answer 3

you been at this one for a while huh?

Answer 4

yes! can't seem to figure it out :(

Answer 5

ok lets go slow (but not that slow)
the slope of
\[y=\color{red}{\frac{1}{2}}x-5\] is ?

Answer 6

hint: it is red

Answer 7

1/2

Answer 8

right
and the perpendicular line with have a slope that is the "negative reciprocal" i.e. flip it and change the sign

Answer 9

2/1?

Answer 10

-2/1*

Answer 11

right, which, on planet earth, we usually just call \(-2\)

Answer 12

haha right

Answer 13

now we got the slope
the point is \((2,-7)\) and they want you to plug all this in to the "point - slope" formula
\[y-y_1=m(x-x_1)\]

Answer 14

where you see \(y_1\) put \(-7\)
where you see \(m\) put \(-2\) and
where you see \(x_1\) put \(2\)

Answer 15

so would it be c?

Answer 16

yes, it is always C
how hard was that? ok?

Answer 17

thank you so much!