Shown below is the quadrilateral ABCD.
Calculate the size of the angle .
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Shown below is the quadrilateral ABCD.
Calculate the size of the angle .
To solve this problem, follow these steps:
Step 1: Identify all given angles and understand the setup.
Step 2: Apply the sum of angles in a quadrilateral formula.
Step 3: Calculate the unknown angle.
Now, let's solve:
Step 1: The problem states:
since it's marked as a right angle.
Step 2: Use the sum of angles in quadrilateral : Substituting the known values: Step 3: Simplify and solve for : Therefore, the measure of is .
Thus, the size of angle is .
103
Is DE side in one of the triangles?
Look for the small square symbol at vertex B! This universal symbol always indicates a right angle (90°). Don't rely only on how the angle looks visually.
This is a fundamental property of all quadrilaterals! Just like triangles always sum to 180°, any four-sided figure's interior angles must sum to 360°, no matter what shape it is.
You likely made an arithmetic error! Check your calculation: , not 203°. Always double-check your subtraction.
Yes! In quadrilaterals, angles can be reflex angles (greater than 180°). However, in this problem, all angles appear to be less than 180° based on the diagram.
No! This problem only requires the basic angle sum rule for quadrilaterals. You don't need to know if it's a rectangle, parallelogram, or any other special type.
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