Question

question 7 of 10 the lines shown below are perpendicular. if the green line has a slope of -1/9, what is the slope of the red line? a. -9 b. -1/9 c. 1/9 d. 9

Explanation:

Step1: Recall slope - perpendicular 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 $m_2$

Substitute $m_1 = -\frac{1}{9}$ into $m_1\times m_2=-1$. We get $-\frac{1}{9}\times m_2=-1$. Multiply both sides by - 9, so $m_2 = 9$.

Answer:

D. 9