Find an equation for a line that contains (4, 9) and is perpendicular to the graph of y = 7x + 3/8

Question

Answer choices
1. y = -1/7 x + 9 4/7
2. y = 7x - 15
3. y = 1/7x + 8 5/7

Answer 1

No work needed.

Since you know that the slopes of perpendicular lines must be negative reciprocals of each other, all you have to look at is their slope.
the slope of the given line is 7, so the slope of the new line must be -1/7
Only 1. fits that.

( I would still check if the given point satisfies y = (-1/7)x + 9 4/7 , it does )

Answer 2

thanks