Question

Math help with 2 quick questions. Dont really understand them

Answer 1

if u assume that our proof is wrong then two line should cross each other at a point so it made a triangle .angle 3 and 6 are supplementary that means they are 180 degree together and the angle 9 (in my draw) is another angle of the triangle so if u plus all the angle it's more than 180 degrees that is wrong
here there is a contradiction so be accept that the two line are parallel so they can's cross each other

Answer 2

read what i wrote then summarize it

Answer 3

if i can

Answer 4

okay

Answer 5

we should proof that angle 3=7
here we assume that they're not .we have two choice 3<7 or 3>7
if 3<7 that mean 3+6<180 degrees that mean it two angle of a triangle so our two parallel line cross each other that is a contradiction so we accept that our angles are equal