Question

What is an equation of the line that passes through the point (- 2, 5) and perpendicular to the line whose equation is y = 1/2 * x + 5

Answer 1

y = -2x + 12

Explanation:

Step 1: find the slope

y = 1/2x + 5

The equation of the line is

y = mx + c

m - slope

m = 1/2

Note : if two lines are perpendicular to the other, both lines are negative reciprocal of each other

m = -2

Step 2 : using a point slope form

y - y1 = m( x - x1)

( 2 , 5)

x1 = 2

y1 = 5

y - 2 = -2( x - 5)

y - 2 = -2x + 10

y = -2x + 10 + 2

y = -2x + 12

The equation of the line is

y = -2x + 12