Question

In a quadrilateral ABCD, the measure of the three angles A,B and c of the quadrilateral are 110°, 70°, 80° respectively. Find the measure of the third angle.​

Answer 1

$\huge\underline\mathrm{SOLUTION:-}$

Correct Question:

• In a quadrilateral ABCD, the measure of three angles A, B, C of the quadrilateral are 110°, 70°, 80° respectively. Find the measure of the fourth angle D.

AnswEr:

• The measure of the fourth angle D = 100°.

Given That:

• The measure of A = 110°
• The measure of B = 70°
• The measure of C = 80°

Need To Find:

• The measure of the fourth angle D = ?

ExPlanation:

• The sum of the all angles of a quadrilateral is equal to 360°.

Then,

➠ ∠A + ∠B + ∠C + ∠D = 360°

➠ 110° + 70° + 80° + ∠D = 360°

➠ 260° + ∠D = 360°

➠ ∠D = 360° - 260°

➠ ∠D = 100°

ThereFore:

• The measure of the fourth angle D = 100°.

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