Question

Look at the figure and the conditional statement based on it.
If angle AXO is 23° and angle BXO is 44°, then angle AOB is 134°.

Samantha wrote a two column proof as shown

Answer 1

Which statement describes the error she made in the proof?
Answer

She made an error in statement 5. Measure of angle XOA = 90° + 44° = 134°.

She made an error in statement 5. Measure of angle XOB = (180°– 2 x 44°) = 92°.

She wrote an incorrect reason for statement 5. She should have written the sum of the base angles of an isosceles triangle is 90°.

She wrote an incorrect reason for statement 6. She should have written the sum of linear pair of angles is 180°.
http://assets.openstudy.com/updates/attachments/4fbfb59be4b0964abc82393c-cbrusoe-1337964048171-aaaaaaaaaaaaaaaaaa.jpg

Answer 2

Statement

Reason
1.

Measure of angle AXO = 23°
Measure of angle BXO = 44°

Given
2.

Segment AO is congruent to segment XO.
Segment BO is congruent to segment XO.

Radii of the same circle are equal.
3.

Triangle AOX is isosceles.
Triangle BOX is isosceles.

If two sides of a triangle are congruent, then the triangle is isosceles.
4.

Measure of angle XAO = 23°
Measure of angle XBO = 44°

The base angles of an isosceles triangle are congruent.
5.

Measure of angle XOA = (180°– 2 x 23°) = 134°
Measure of angle XOB = 2 x 23° + 44° = 90°

The sum of the interior angles of a triangle is 180°.
6.

Let measure of angle AOB be w°
Then w + 134 + 92 = 360

The sum of angles around a point is 360°.
7.

w = 360 – 226 = 134
Therefore measure of angle AOB is 134°.

Subtraction property of equality.

Answer 3

Hey, did you finish 10-2?

Answer 4

yes but I'm trying to finish this before I do anything else

Answer 5

@aroub @ash2326 @zepp

Answer 6

Sorry..

Answer 7

Is it the third one? She made an error in statement 5. Measure of angle XOA = (180°– 2 x 23°) = 134°.

Answer 8

No clue, Im not on this section yet.

Answer 9

Measure of angle XOB = 2 x 23° + 44° = 90°
it should be
angle XOB= \(180-2\times 44=92\)

Answer 10

The first line is the error she mad

Answer 11

she made an error in statement 5. Measure of angle XOB = (180°– 2 x 44°) = 92
do you get my point @J.L. ?

Answer 12

That's not any of the answer choices though @ash2326

Answer 13

It is:)

Which statement describes the error she made in the proof?
Answer

She made an error in statement 5. Measure of angle XOA = 90° + 44° = 134°.

\(\longrightarrow\)She made an error in statement 5. Measure of angle XOB = (180°– 2 x 44°) = 92°.

She wrote an incorrect reason for statement 5. She should have written the sum of the base angles of an isosceles triangle is 90°.

She wrote an incorrect reason for statement 6. She should have written the sum of linear pair of angles is 180°.
http://assets.openstudy.com/updates/attachments/4fbfb59be4b0964abc82393c-cbrusoe-1337964048171-aaaaaaaaaaaaaaaaaa.jpg

Answer 14

That last choice should've had said She wrote an incorrect reason for statement 5...NOT 6
My bad

Answer 15

then also the answer will be the same

Answer 16

do you understand where she made error?

Answer 17

I gave you the wrong choices sorry!
She wrote an incorrect reason for statement 5. She should have written the sum of the base angles of an isosceles triangle is 90°.

She made an error in statement 5. Measure of angle XOB = 2 x 23° + 44° = 90°.

She made an error in statement 5. Measure of angle XOA = (180°– 2 x 23°) = 134°.

She wrote an incorrect reason for statement 5. She should have written the sum of linear pair of angles is 180°.

Answer 18

This is the one
She made an error in statement 5. Measure of angle XOB = 2 x 23° + 44° = 90°.
\[\text{correction:It would be angle XOB=180-2*44=92}\]

Answer 19

Thank you so much! I have a couple other questions...do you think you could help me?