Given:In quadrilateral WXYZ , and bisect each other at point A. Prove: Quadrilateral WXYZ is a parallelogram.

Statement

Reason

1. and bisect each other. given
2. WA = YA
XA = ZA

definition of bisection

3. m∠YAZ = m∠XAW

Vertical Angles Theorem

4.

SAS criterion for congruence

5. ∠ YWX ≅ ∠WYZ

Corresponding angles of congruent triangles are congruent.

6. ||

converse of Alternate Interior Angles Theorem

7. m∠XAY = m∠ZAW

Vertical Angles Theorem

8. ∆XAY ≅ ∆ZAW

SAS criterion for congruence

9. ∠XZW ≅ ∠ZXY

Corresponding angles of congruent triangles are congruent.

10. ||

converse of Alternate Interior Angles Theorem

11. Quadrilateral WXYZ is a
parallelogram.

definition of parallelogram

Use addition and subtraction to simplify the following polynomials. a. add polynomials: (3 – 4x + 8x^2) + (–6 + 2x – 5x^2) step 1: rewrite the polynomials without the parentheses. step 2: write the polynomial in descending order and use parentheses around like terms. step 3: add the like terms identified in step 2 to simplify the polynomial. b. subtract polynomials: (3x – 5 – 7x^2) – (–2 + 6x^2 – 5x) step 1: rewrite the polynomials without the parentheses. remember to multiply each term in the second parentheses by –1. show your work. step 2: write the polynomial in descending order and use parentheses around like terms. step 3: add the like terms identified in step 2 to simplify the polynomial.

Which expression is equivalent to7_/x^2 ÷ 5_/y^3? assume y# 0

Atriangular field has sides of lengths 21, 39, and 41 yd. find the largest angle. (round your answer to the nearest degree.)