Hector types at a rate of 40 words per
minute. The equation w = 40m describes the
relationship between w, the number of words
he types, and m, the number of minutes he
spends typing. Which statement is true?
A The rate at which Hector types depends
on the number of minutes he spends
typing.
B The number of minutes he spends typing
depends on the number of words he types.
C The number of words he types depends on
the number of minutes he spends typing.
D The rate at which Hector types depends
on the number of words he types.

Statement reason 1. δabc is similar to δced. given 2. 3. definition of slope 4. slope of slope of definition of slope 5. slope of × slope of multiplying the slopes 6. slope of × slope of substitution property of equality 7. slope of × slope of simplifying the right side the table contains the proof of the relationship between the slopes of two perpendicular lines. what is the reason for statement 2? a. parallel line segments that meet a common perpendicular line are proportional in length. b. the lengths of vertical and horizontal sides in congruent triangles are in a common ratio. c. trigonometric identities determine the lengths of the legs in a right triangle. d. corresponding side lengths in similar triangles are proportional in length.