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Bullet_Dodger
04-04-2006, 09:31 PM
I know this is kind of ridiculous, but I am weeks behind my work due to an illness, and I have no idea what I'm doing. Any help is appreciated. Thanks.

1. Given quadrilateral PQRS with vertices P (-2,3) Q (1,0) R (7,6) and S (0,5) prove that PQRS is a trapezoid.

2. Prove, using coordinate geometry, that the diagonals of isosceles trapezoid FISH with vertices F (2a, b) I (5a, b) S (7a,0) and H (0,0) are congruent

4. Given: Parallelogram ABCD
Line CE is perpendicular to Line AB
Line CF is perpendicular to Line AD
Prove: Triangle DCF ~ Triangle BCE

5. Given: Triangle ABC is isosceles with base Line AC
Line BD bisects angle ABC
Prove: Triangle ADB is congruent to Triangle CDB

6. Given: R is the midpoint of Line QS
QS bisects Line PT
Prove: Line PQ is congruent to Line TS

7. Given: Triangle BAT, line CBTD and Line AB are perpendicular to CD

Write an indirect proof to show that line AT is not perpendicular to Line CD

TomCollins
04-04-2006, 09:46 PM
1. Given quadrilateral PQRS with vertices P (-2,3) Q (1,0) R (7,6) and S (0,5) prove that PQRS is a trapezoid.
Trapezoids have two parallel edges. Draw it out, figure out which ones are parallel, then prove it with math

Bullet_Dodger
04-04-2006, 11:29 PM
[ QUOTE ]
1. Given quadrilateral PQRS with vertices P (-2,3) Q (1,0) R (7,6) and S (0,5) prove that PQRS is a trapezoid.
Trapezoids have two parallel edges. Draw it out, figure out which ones are parallel, then prove it with math

[/ QUOTE ]

Ill try that, thanks

Nottom
04-05-2006, 01:16 AM
[ QUOTE ]
2. Prove, using coordinate geometry, that the diagonals of isosceles trapezoid FISH with vertices F (2a, b) I (5a, b) S (7a,0) and H (0,0) are congruent

[/ QUOTE ]

Find the 2 non-parallel sides and compute their lengths.

[ QUOTE ]
4. Given: Parallelogram ABCD
Line CE is perpendicular to Line AB
Line CF is perpendicular to Line AD
Prove: Triangle DCF ~ Triangle BCE

[/ QUOTE ]

I'm not sure what the picture looks like here, but I'd imagine you will be using ASA to prove congruence.

[ QUOTE ]

5. Given: Triangle ABC is isosceles with base Line AC
Line BD bisects angle ABC
Prove: Triangle ADB is congruent to Triangle CDB

[/ QUOTE ]

Use AAS

[ QUOTE ]

6. Given: R is the midpoint of Line QS
QS bisects Line PT
Prove: Line PQ is congruent to Line TS

[/ QUOTE ]
I assume PT passes through point R.
If so you can use SAS to show triangles QRP and SRT are congruent.


[ QUOTE ]

7. Given: Triangle BAT, line CBTD and Line AB are perpendicular to CD

Write an indirect proof to show that line AT is not perpendicular to Line CD

[/ QUOTE ]

I can't really picture this. But I think you just assume AT is perp but then angle BAT = 0 which isn't true since ABT is a triangle. Thus the assumption can't be true.