Question

Can you help me with math (triangles)? Do only question 6

Answer 1

`\sf\\\textsf{There is a property of parallelogram that says`

Here's a proof of the theorem. See the image as a reference.

`\sf\\1.\ \textsf{In triangles AOB and BOC,}\\i.\ \angle OAD=\angle OCB\ (A)\ \ \ [\textsf{AD//BC, alternate angles}]\\ii.\ AD=BC\ (S)\ \ \ [\textsf{Opposite sides of parallelogram are equal.}]\\iii.\ \angle ODA=\angle OBC\ (A)\ \ \ [\textsf{AD//BC, alternate angles.}]\\iv.\ \triangle AOB\cong \triangle BOC\ \ \ [\textsf{By A.S.A. axiom}]\\\\2.\ AO=OC\ and\ BO=OD\ \ \ [\textsf{Corresponding sides of congruent triangles are}\\\textsf{equal.]}`

Two figures are said to be congruent if they have same shape and size. Two figures are said to be similar if they have same shape.

Answer 2

AB = BC
10 = 10

AC = AB + BC = 10 + 10 = 20

BD = BE
20 = 20

DE = BD + BE

DE = 20 + 20

DE = 40