Answer:
C. -4/3
Explanation:
Perpendicular lines have negative reciprocal slopes.
We know that line m is perpendicular to line l.
Line l has a slope of 3/4. To find the slope of line m, find the negative reciprocal of 3/4. Negate the fraction and find the reciprocal.
Negative: switch the sign
3/4 --> -3/4
Reciprocal: switch the numerator (top number) and denominator (bottom number)
-3/4 --> -4/3
Line m has a slope of -4/3 and C is correct.