Question

what is the equation of the line that is perpendicular to the line y=3/5x+10 and passes through the point (15,-5)

Answer 1

`y = -\frac53x + 20`

Explanation:

Hello!

A line that is perpendicular to another has an opposite-reciprocal slope.

Meaning:

• Flip the sign (+/-)
• Flip the fraction

The slope perpendicular to 3/5 would be -5/3.

We can solve for the y-intercept by plugging in the x and y values given from the coordinate into the equation with out new slope.

Solve for B

• 
  `y = -\frac53x + b`
• 
  `-5 = -\frac53(15) + b`
• 
  `-5 = -25 + b`
• 
  `20 = b`

The y-intercept of the new line is 20.

The equation is
`y = -\frac53x + 20`