Question

Three angles of a quadrilateral are equal.The fourth angle is 120°.what is the measure of the equal angles.​

Answer 1

$\underline\color{black}\mathfrak{\underline{Answer}}$

80°

$\underline\color{black}\mathfrak{\underline{Explanation}}$

Given:

• Three angles of quadrilateral are equal
• The measure of Fourth angle is 120°

To find:

• Measure of equal angles

Solution:

Let the equal angles be X

$\fbox{\rm The \:sum \:of \:4\:angles\: of\: quadrilateral = 360°}$

⇒X + X + X + 120° = 360°

⇒3X + 120 = 360

⇒3X = 360 - 120

⇒3x = 240

⇒X = 240/3

∴ Measure of equal angles = 80°

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$\underline\color{black}\mathfrak{\underline{Verification}}$

80 + 80 + 80 + 120

= 360°