Question

In the figure below, 1 and 2 are adjacent angles:



Write an indirect proof proving that the sum of 1 and 2 is 180°.

Answer 1

could someone help

Answer 2

please

Answer 3

well obviously one of the angles is like 45 degrees and the other 135 degrees i think

Answer 4

I need to write an indirect proof

Answer 5

oh i can only do direct proof sorry

Answer 6

It's ok xD

Answer 7

if i may make a suggestion you could ask a qualified helper.

Answer 8

i dont have those coins you need

Answer 9

oh u need the coins to ask one?

Answer 10

ok sorry i couldent help but i gtg

Answer 11

ok

Answer 12

Assume that m<1+m<2 is not equal to 180. CA and CB are opposite rays. <1 and <2 are adjacent angles . 1 and < 2 are supplementary => m<1+m<2 = 180 . => the assumption m<1+m<2 is not 180 is false. =>the sum of two adjacent angles is 180.

Answer 13

you dont need the reasoning when doing an indirect proof?

Answer 14

@ AlexandervonHumboldt2

Answer 15

well you need ......hm

Answer 16

...

Answer 17

what do i need

Answer 18

@AlexandervonHumboldt2

Answer 19

anyone

Answer 20

If angles 1 & 2 were not supplementary, then the three angles about the point C would not sum to 360°.