Question

Find the equation of the line through point (8, -9) and perpendicular to 3x +8y =4

Answer 1

Answer:

y = 8/3x - 91/3

*view attached graph*

Step-by-step explanation:

3x +8y =4

-3x    -3x

8y = -3x + 4

/8      /8

y = -3/8x + 1/2

Perpendicular lines have reciprocal slopes. So, the slope of -3/8 will now be 8/3

y = mx + b

y = 8/3x + b

-9 = 8/3(8) + b

-9 = 64/3 + b

3(-9 = 64/3 + b)

-27 = 64 + 3b

-64 -64

-91 = 3b

/3    /3

-91/3 = b

y = 8/3x - 91/3

Check your answer using (8, -9):

y = 8/3x - 91/3

-9 = 8/3(8) - 91/3

-9 = 64/3 - 91/3

-9 = -27/3

-9 = -9

This statement is true.

Hope this helps!