Question

Select the correct answer.

A software designer is mapping the streets for a new racing game. All of the streets are depicted as either perpendicular or parallel lines. The equation of the lane passing through A and B is -7x + 3y = -21.5. What is the equation of the central street PQ?

A. -3x + 4y = 3

B. -1.5x − 3.5y = -31.5

C. 2x + y = 20

D. -2.25x + y = -9.75

Answer 1

$-7x + 3y = -21.5 / : 3$

$\large\frac{-7}{3}x+y=-\frac{43}{6}$ $\to y = \frac{7}{3}x-\frac{43}{6}$

perpendicular -> $k_1*k_2=-1$

$\large\frac{7}{3}*k_2=-1 \to k_2=-\frac{3}{7}$

B) $-1.5x-3.5y=-31.5$

$y = -\frac{3}{7}x+9$

Answer is B