Question

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Explanation:

Step1: Recall the triangle - angle sum theorem

The sum of the interior angles of a triangle is \(180^{\circ}\). So, if the angles of the triangle are \(53^{\circ}\), \(72^{\circ}\), and \(a^{\circ}\), then \(53 + 72+a=180\).

Step2: Simplify the left - hand side of the equation

First, calculate \(53 + 72\). \(53+72 = 125\). So the equation becomes \(125 + a=180\).

Step3: Solve for \(a\)

Subtract \(125\) from both sides of the equation. \(a=180 - 125\).

Answer:

\(a = 55\)