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Excel in math and science
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Geometry
Angles and Lines
Excel in math and science
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It's hard to learn from lectures and videos
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Concept Quizzes
How many acute angles does an obtuse triangle have?
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
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by Brilliant Staff
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
examples, and problems from the community.
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by Brilliant Staff
Angles \(ABC\) and \(CBD\) are adjacent with common vertex \(B\) and common edge \(\overline{BC}.\) If \(\angle ABC={51}^\circ\) and \(\angle CBD={40}^\circ,\) which of the following is true of \(\angle ABD?\)
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
examples, and problems from the community.
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by Brilliant Staff
If \(\angle A\) is an acute angle, \(\angle B\) is a right angle and \(\angle C\) is an obtuse angle, which of the following is true of \(\angle A+\angle B+\angle C ?\)
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
examples, and problems from the community.
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That seems reasonable.
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by Brilliant Staff
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, conceptual quizzes.
Our wiki is made for math and science
Master advanced concepts through explanations,
examples, and problems from the community.
Used and loved by 4 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
Your answer seems reasonable.
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That seems reasonable.
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by Brilliant Staff