Read the real-world situation and substitute in values for the projectile motion formula. Then solve the resulting quadratic equation by factoring to answer the question. An airplane pilot jumps out of an airplane and has an initial velocity of 60 feet per second downwards. How long does it take to fall from 1000 feet to 900 feet before the parachute opens? The pilot falls for seconds before the parachute opens.

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.