Question

Consider the line y=-7x+8. -- Find the equation of the line that is perpendicular to this line and passes through the point (8. -3). Find the equation of the line that is parallel to this line and passes through the point (8. –3).

Equation of perpendicular line:

Equation of parallel line:​

Answer 1

Explanation:

Perpendicular formula

m1 * m2 = - 1

Givens

m1 = - 7

m2 = ??

Solution

-7 * m2 = -1

m2 = 1/7

y = 1/7 x + b

x = 8

y = -3 Substitute these values into y = 1/7 x + b

-3 = (1/7)*8 + b

-3 = 8/7 + b Subtract 8/7 from both sides

-3 - 8/7 = b

-4 1/7 = b

Answer (perpendicular line) y = (1/7) x - 4 1/7 or

Answer (perpendicular line) y = (1/7) x - 4.14

Parallel line

Nothing changes except you have a different y intercept.

y = -7x + b

x = 8

y = -3 Substitute these values into y = -7x + b

-3 = -7*8 + b

-3 = - 56 + b

-3 + 56 = b

b = 53

Equation Parallel line: y = -7x + 53