Respuesta :

The m∠POS would be - 65° by the angle addition postulate and substitution postulate.

Given, m∠POQ = 19° , m∠QOR = 31° and m∠ROS = 15°

Angle Addition Postulate is the measure of the larger angle is the sum of the measures of the two smaller angles.

Substitution postulate states that a quantity may be substituted for its equality in any expression.

Then substitute the angle  measurements into the resulting equation to find, m∠POS:

m∠POQ + m∠QOR = m∠POR (by angle addition)

m∠POR + m∠ROS = m∠POS (by substitution)

m∠POS = m∠POQ + m∠QOR + m∠ROS

= 19° + 31° + 15°

= 65°

Thus, the m∠POS would be - 65° by the angle addition postulate and substitution postulate.

Learn more about Angle addition postulate here:

brainly.com/question/14957499

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