The table shows the proof of the relationship between the slopes of two perpendicular lines. what is the missing statement in step 6? a) slope of ac x slope of dc= ec/dc x dc/ec b) slope of ac x -slope of dc=1 c) slope of ac x slope of dc=1 d) slope of ac x slope of dc=-ec/dc x dc/ec statement 1. ac←→⊥cd←→ (view diagram) δabc is similar to δced. 2. (this statement is intentionally left blank.) 3. abbc = ecde 4. slope of ac←→ = -abbc slope of dc←→ = deac 5. slope of ac←→ × slope of dc←→ = -abbc×deec 6. ? 7. slope of ac←→ × slope of dc←→ = -1 simplifying the right side reason 1. given 2. property of similar triangles 3. property of proportion 4. definition of slope 5. multiplying the slopes 6. substitution property of equality 7. simplifying the right side