Where did the 180 degrees go?
Hana found the third angle of a triangle with angles 65 and 42 by writing 107. She added the two she had and never finished the problem.
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1 lesson for “Triangle angle sum”
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What is sin A when the opposite side is 3 and the hypotenuse is 5?
Trigonometry begins with one idea: a ratio of two sides. Label the sides for your chosen angle, and the ratio is mechanical.
Try this lessonIn a 30-60-90 triangle, what is the hypotenuse if the short leg is 5?
A 30-60-90 triangle has fixed ratios between its sides. Know one side and the other two follow without any trigonometry.
Try this lessonWhat is sin of a 30-degree angle on the unit circle?
On the unit circle, every point's coordinates are (cos, sin). Learn a few landmarks and the special angles are solved.
Try this lessonIs water's molar mass 17 or 18 g/mol?
The subscript 2 in H2O is easy to miss in a molar mass. Count it once, and every conversion after stays right.
Try this lessonWhat is the net force when pulls go against each other?
You said a 100 N pull right and a 40 N pull left give 140 N. They fight: the net force is the difference, 60 N, and it points the stronger way.
Try this lessonWhich pair of numbers factors x^2 + 7x + 12?
A trinomial like x^2 + 7x + 12 hides a pair of numbers. Find the pair, and the factored form falls into place.
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