Question

3. If a parallelogram has one angle
measuring 60°, then find the measure of
the other angles.​

Answer 1

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Here, ABCD is a  parallelogram.

We know one angle of this parallelogram is 60°

So, Let us Assume that , ∠A = 60° .

We know that in a parallelogram the opposite sides and opposite angles are equal.

$\implies$ ∠A = ∠C = 60°

Total angle sum of a parallelogram is 360°

$\implies$ ∠A + ∠B + ∠C + ∠D = 360°$\longrightarrow$ (1)

We know the value of ∠A and ∠C , substituting it in (1) , we get

60° + ∠B + 60° + ∠D = 360°

∠B + ∠D = 360° - 120°

∠B + ∠D = 240°$\longrightarrow$ (2)

Since, ∠B and ∠D are opposite they are equal.

So ,

∠B = ∠D $\longrightarrow$ (3)

Substituting value of ∠B = ∠D  in (2), we get,

2∠B = 240°

∠B = 240/2 = 120°

Also ,

∠D = 120° [ Since ∠B = ∠D]

Answer 2

Step-by-step explanation:

i hope its help you.......