Question

The equation of a line is y=-1/2x-2. What is the equation of the line that is perpendicular to the first line and passes through the point (2, –2)?
A.
y = 2x – 2
B.
y=1/2x - 3
C.
y = 2x – 6
D.
y = –2x + 2

Answer 1

The slope in the equation given is -1/2. Since we are looking for a perpendicular line, we need he negative reciprocal of that slope. All that means is " flip " the slope and change the sign. Therefore, the negative reciprocal of -1/2 is 2/1 or just 2.
now we use y = mx + b (and solve for b)
slope(m) = 2
(2,-2) x = 2 and y = -2
now we sub
y = mx + b
-2 = 2(2) + b
-2 = 4 + b
-2-4 = b
-6 = b
so your perpendicular line is : y = 2x - 6

Answer 2

Thank you!