Its an indirect proof, so 3 steps :-
1) you start with the opposite of wat u need to prove
2) arrive at a contradiction
3) concludeReport · 29/6/2015261
since you wanto prove 'diagonals of a parallelogram bisect each other', you start wid the opposite of above statement, like below :- step1 : Since we want to prove 'diagonals of a parallelogram bisect each other', lets start by assuming the opposite, that the diagonals of parallelogram dont bisect each other.Report · 29/6/2015261
Since, we assumed that the diagonals dont bisect each other,
OC≠OA
OD≠OBReport · 29/6/2015261
Since, OC≠OA, △OAD is not congruent to △OCBReport · 29/6/2015261
∠AOD≅∠BOC as they are vertical angles,
∠OAD≅∠OCB they are alternate interior angles
AD≅BC, by definition of parallelogram
so, by AAS, △OAD is congruent to △OCBReport · 29/6/2015261
But, thats a contradiction as we have previously established that those triangles are congruentReport · 29/6/2015261
step3 :
since we arrived at a contradiction, our assumption is wrong. so, the opposite of our assumption must be correct. so diagonals of parallelogram bisect each other.
Answer:
point-slope form: 
Step-by-step explanation:
hope this helps :)
5. 6√3
6. x = 10√3 y = 30
7. x = 34 y = 17√3
8. 30
9. SinA = 3/5 CosA = 4/5
10. Tan20 = 9/x
Multiply both sides by x to get it on the other side
x(tan20) = 9
Divide 9 by tan20 to get x.
x = 9/tan20
x = 24.7
Add the 75 and 79 which gives u 154
then subtract it by 180 and should give you 26 as your final answer
