What is the value of angle a in the given diagram?

here are the solutions to the remaining problems.

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The image shows a right angle, indicated by the square symbol, which measures $90^\circ$. This angle is divided into two smaller angles: $a$ and $27^\circ$. The sum of these angles must equal $90^\circ$.

Step 1: Set up the equation for the sum of the angles.

$$a + 27^\circ = 90^\circ$$

Step 2: Subtract $27^\circ$ from both sides of the equation to solve for $a$.

$$a = 90^\circ - 27^\circ$$ $$$$