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A, B & C lie on a straight line. D, C & E lie on a different straight line. Angle y = 117° and angle z = 63°. Work out x

User Haacked
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Consider the below figure attached with this question.

Given:

A, B & C lie on a straight line. D, C & E lie on a different straight line.


\angle y=117^\circ,\angle z=63^\circ

To find:

The value of x.

Solution:

A, B & C lie on a straight line.


m\angle ABD+m\angle DBC=180^\circ (Linear pair)


y+m\angle DBC=180^\circ


m\angle DBC=180^\circ-y

According to the exterior angle theorem, the measure of an exterior angle of a triangle is equal to the sum of two opposite interior angles.


m\angle DBC+m\angle BDC=m\angle BCE (Exterior angle theorem)


180^\circ-y+z=x


180^\circ-117^\circ +63^\circ =x


126^\circ =x

Therefore, the value of x is 126 degrees.

A, B & C lie on a straight line. D, C & E lie on a different straight line-example-1
User Kryptonkal
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