Question

in fig. show that
(I)ab|| cd
ii) cd|| ef
iii) ab|| ef

Answer 1

HEY !!

HERE IS YOUR ANSWER,

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■ (a) to show = ab ll CD

ABC = 40

BCD = 20 + 20 = 40

There alternate interior angles are equal so ab ll CD.

■ (b) to show = CD ll ef

stretch the line CD .. let the angle formed is x.

x + 20 +20 = 180 ( linear pair )

x + 40 = 180

x = 180 - 40

x = 140

x + BCD = FEC ( ALTERNATEINTERIOR ANGLES )

140 + 20 = 160

160 = 160

Their alternate interior angles are equal so CD ll EF.

■ (c) to show = ab ll ef

stretch line EF angle formed on E named y .

A triangle formed ECG.

y + 160 = 180 ( linear pair )

y = 180 - 160

y = 20 ( GEC)

EGC + 20 + 20 = 180 ( angle sum property )

EGC + 40 = 180

EGC = 180 - 40

EGC = 140

EGC + BGE = 180 ( LINEAR PAIR )

140 + BGE = 180

BGE = 180 - 140

BGE = 40

Their consecutive angle are equal so ab ll ef.

✔ HENCE PROVED

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HOPE IT HELPS U !!

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