Question

Write an equation of the line that is perpendicular to 2x + 4y = 6 and passes through the point (6, 4) ). es A ) y = 2x + 4 B) y = 2x - 8 y = - 2x + 16 y = - 1/2 * x + 4

Answer 1

B - y = 2x - 8

Explanation:

Step 1: find slope

2x + 4y = 6

4y = -2x + 6

Make y the subject of the formula

y =( -2x + 6)/4

We can separate to get the slope

y = -2x/4 + 6/4

y = -x/2 + 3/2

Slope m = -1/2

Step 2: using a point slope form equation

y - y1 = m ( x - x1)

Note: if two lines are perpendicular to the other, it is always a negative reciprocal of each other

ie m = 2

Substitute m into the equation

y - y1 = 2(x - x1)

Step 3: sub the point

( 6 , 4)

x1 = 6

y1 = 4

y - 4 = 2( x - 6)

Step 4 : using a slope intercept form equation

Open the bracket

y - 4 = 2x - 12

y = 2x - 12 + 4

y = 2x - 8

The equation of a line is

y = 2x - 8