Question

4. ABCD is a quadrilateral.
Is AB + BC + CD + DA > AC + BD?
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Answer 1

Step-by-step explanation:

draw any quadrilateral ABCD

join AC and BD

now in triangle ABC

AB+BC>AC (property of triangle).....1

now similarly in triangle ACD

AD+DC>AC.....2

now in triangle DAB

DA+ AB> DB......3

now in triangle DCB

DC+ CB> DB ......4

add 1 ,2, 3, 4

2(AB+ BC +CD+ DA)=2(AC+BD)

AB+ BC+CD+DA>AC+BD

hence prove d