Question

If ∠A and ∠B are two adjacent angles of a parallelogram. If ∠A = 60°, then ∠B = ?
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Answer 1

$\sf\large\purple{Given⟹}$

ABCD is a parallelogram and $\tt ∠A=60°$

$\sf\large\green{Solution⟹}$

We know that opposites angles of a parallelogram are equal.

Therefore,

${\sf{\boxed{∠A=∠C=60°}}}$

${\sf {\underline{\boxed{Formula \to ∠A+∠B=180°}}}}$

$\sf\implies 60° +∠B=180°$

$\sf\implies ∠B=120°$

${\bold{\sf{\implies{\blue{ ∠B=∠D=120°}}}}}$ (opposite angles of parallelogram)

Answer 2

Question:-

➡ If ∠A and ∠B are two adjacent angles of a parallelogram and ∠A=60°, find ∠B.

Answer:-

➡ The value of ∠B is 120°

Solution:-

➡ Given, ∠A = 60°

➡ To find:- ∠B

We know that,

Sum of adjacent angles of a Parallelogram is 180°

So, let us assume that ∠B=x

According to given condition,

60° + x = 180°

➡ x = 180° - 60°

➡ x = 120°

➡ ∠B = 120°

Hence, the value of ∠B is 120°.

Verification:-

∠A + ∠B

= 60° + 120°

= 180°

Hence, value of ∠B is 120°.