Find the value of x, proportions in similar triangles

40 points. given: two congruent angles ∠c and ∠r are supplementary. prove: ∠r and ∠c are both right angles. it doesn't have to be exactly 10 rows.statements reasons1. 1. 2. 2. 3. 3. 4. 4. 5. 5. 6. 6. 7. 7. 8. 8. 9. 9. 10. 10.

Can someone show me step by step how to do this?

One of the solutions to x2 - 2x – 15 = 0 is x = -3. what is the other solution? ox=-5 ox= -1 0 x=1 x = 5