Question

question 3 of 10 the lines shown below are perpendicular. if the green line has a slope of -\frac{1}{9}, what is the slope of the red line? a. -\frac{1}{9} b. 9 c. \frac{1}{9} d. -9

Explanation:

Step1: Recall slope - perpendicular line rule

The product of slopes of two perpendicular lines is - 1. Let the slope of the green line be $m_1=-\frac{1}{9}$ and the slope of the red line be $m_2$. Then $m_1\times m_2=-1$.

Step2: Solve for $m_2$

We have $-\frac{1}{9}\times m_2=-1$. Multiply both sides by - 9 to isolate $m_2$. So $m_2 = 9$.

Answer:

B. 9