Question

ABCD is a parallelogram in which angle DAB=70 and angle CBD=55.find angle CDB and angle ADB​

Answer 1

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Given:-

• ABCD is a Parallelogram in which ∠DAB = 70°, ∠CBD = 55°

To Find:-

• The ∠CBD and ∠ADB.

Concept used:-

• As we know that In a Parallelogram Sum of adjacent sides is equal to 180°.

• If two line is Parallel then Alternate angles are equal.

,

Now,

AD || BC and AB is Transversal.

→ ∠CBD = ∠ADB ( Alternate interior angle )

→ ∠ADB = 55°

Therefore,

→, ∠A + , ∠D = 180° ( Sum of adjacent side)

→ , ∠DAB + , (∠ADB + BDC) = 180°

→ 70° + ∠55° + ∠CDB = 180°

→ 125° + ∠CDB = 180°

→ ∠CDB = 180° - 125

→ ∠CDB = 55°

Answer 2

Given:-

• ☆ ABCD is a Parallelogram in which

∠DAB = 70°, ∠CBD = 55°

To Find:-

• ☆The value of ∠CBD and ∠ADB.

Note this:-

• ☆In a Parallelogram Sum of adjacent sides is equal to 180°.

• ☆If two line is Parallel then Alternate angles are equal.

Solution:-

AD || BC and AB is Transversal.

$\sf→ ∠CBD = ∠ADB ( Alternate \: interior \: angle )$

$\sf→ ∠A + , ∠D = 180° ( Sum \: of \: adjacent \: side)$

$\sf→ ∠DAB + (∠ADB + BDC) = 180°$

$\sf \to 70° + ∠55° + ∠CDB = 180°$

$\sf→ 125° + ∠CDB = 180°$

$\sf→ ∠CDB = 180° - 125$

$\boxed{ \sf{{→ ∠CDB = 55°}}}$