Geometry 2.5 Use Parallel Lines and Transversals

When sunlight enters a drop of rain, different colors of light leave the drop at different angles.

Goal: I can classify and calculate angles formed by parallel lines and transversals [G.CO.9]

Tiling Activity

Justify your answer.

Find the measure of the numbered angles. Justify your answer.

6.

21

100˚3

4

7.

8. Solve for x and y.

135o

(x – 30)o

y˚

9. Solve for x.

Assignment:

2.5 worksheet

If //, corresp. ∠s ≅

If //, alt. int. ∠s ≅If //, consecutive int. ∠s are supplementary

If //, alt. ext. ∠s ≅

Vert. ∠s ≅Linear Pairs are supplementary

Summary

Geo 2.5 wksht answers1. 65˚, If ||, then corr ∠s are ≅2. 71˚, If ||, then alt-int ∠s are ≅3. 63˚, If ||, then same- side int ∠s are supp.4. 120˚, If ||, then alt-ext ∠s are ≅5. 125˚, If ||, then linear pairs are supp.

6. 150˚; If ||, then corr ∠s are ≅ 150˚; vert ∠s are ≅

7. 122˚; If ||, then alt-int ∠s are ≅ 58˚; If ||, then same- side int ∠s are supp.

8. m∠1 = 90˚, m∠2 = 115˚ m∠3 = 65˚

9. m∠1 = 100˚, m∠2 = 80˚ m∠3 = 100˚

10. corresponding ∠s x = 7

11. same-side int ∠s x = 4

12. alt-int ∠s x = 8

13. alt-ext ∠s x = 6

14. linear pair x = 9

15. vertical ∠s x = 12

16. x = 145, y = 15 17. x = 20, y= 10