Advertisements
Advertisements
Question
In the below fig, arms BA and BC of ∠ABC are respectively parallel to arms ED and EF of
∠DEF. Prove that ∠ABC + ∠DEF = 180°.
Solution
Given AB || DE, BC || EF
To prove: `∠`ABC + `∠`DEF =180°
Construction: produce BC to intersect DE at M
Proof: Since AB || EM and BL is the transversal
`∠`ABC = `∠`EML [Corresponding angle] ……(1)
Also,
EF || ML and EM is the transversal
By the property of co-interior angles are supplementary
`∠`DEF + `∠`EML = 180°
From (i) and (ii) we have
∴`∠`DEF + `∠`ABC = 180°
APPEARS IN
RELATED QUESTIONS
In the given figure, ∠PQR = ∠PRQ, then prove that ∠PQS = ∠PRT.
Write the supplement of the following angles .
138°
In the below Fig, ∠AOC and ∠BOC form a linear pair. if a − 2b = 30°, find a and b.
In the below fig, AOC is a line, find x.
In below figure, lines AB and CD intersect at O. If ∠AOC + ∠BOE = 70° and ∠BOD =
40°, find ∠BOE and reflex ∠COE.
statement are true and false
Angles forming a linear pair can both the acute angles.
In below fig, AB CD and ∠1 and ∠2 are in the ratio 3 : 2. Determine all angles from 1 to 8.
Prove that if the two arms of an angle are perpendicular to the two arms of another angle, then the angles are either equal or supplementary
Two unequal angles of a parallelogram are in the ratio 2 : 3. Find all its angles in degrees .
Fill in the blank in the following to make the statement true:
If two parallel lines are intersected by a transversal, then each pair of corresponding
angles are _______