What is the size of the missing angle?
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What is the size of the missing angle?
To find the size of the missing angle, we will use the property that the sum of angles on a straight line is . Given that one angle is , we can calculate the missing angle using the following steps:
Therefore, the size of the missing angle is .
100°
If one of two corresponding angles is a right angle, then the other angle will also be a right angle.
A straight line forms a straight angle, which by definition measures exactly 180°. When you split this into two or more angles, they must add up to the original 180°.
Supplementary angles add to 180° (straight line), while complementary angles add to 90° (right angle). Remember: Supplementary = Straight = 180°!
Yes! You can have 3, 4, or more angles on a straight line. The key rule remains the same: all angles must add up to 180° total.
Look for angles that share a common vertex and whose sides form a straight line. In diagrams, this appears as angles sitting next to each other on a line.
Check your work! Angles are always positive. If you get negative, you likely subtracted in the wrong direction or misread the given angle measure.
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