Angles (estimating angle size)

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Question 1

Two of the angles are obtuse angles.
Which angle is closest in size to 140°?

1st diagram shows angle greater than 180 degrees and less than 270 degrees 2nd diagram shows angle greater than 90 degrees and less than 180 degrees 3rd diagram shows an angle of 90 degrees 4th diagram shows angle greater than 90 degrees and less than 180 degrees but closer to 180 degrees than diagram 2

Solution

140° is the size of an obtuse angle.
The two obtuse angles are shown below.

2nd diagram shows angle greater than 90 degrees and less than 180 degrees 4th diagram shows angle greater than 90 degrees and less than 180 degrees but closer to 180 degrees than diagram 2

140° = 90° + 50°, about one and a half right angles. The angle to the left is the correct choice.


Types of angles

Question 2

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