1. Given any triangle ABC with sides BC=a, AC=b and AB=c, the following are true :
i) the larger the angle, the larger the side in front of it, and the other way around as well. (Sine Law) Let a=20 in, then the largest angle is angle A.
ii) Given the measures of the sides of a triangle. Then the cosines of any of the angles can be found by the following formula:
a^{2}=b ^{2}+c ^{2}-2bc(cosA)
2.
20^{2}=9 ^{2}+13 ^{2}-2*9*13(cosA) 400=81+169-234(cosA) 150=-234(cosA) cosA=150/-234= -0.641
3. m(A) = Arccos(-0.641)≈130°,
4. Remark: We calculate Arccos with a scientific calculator or computer software unless it is one of the well known values, ex Arccos(0.5)=60°, Arccos(-0.5)=120° etc
Answer:
22 grams
Step-by-step explanation:
loses 50% of it's mass per 22 years
so after 22 years the mass would be 44 grams
22 years later would leave 50% of 44 grams = 22 grams
Answer:
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Step-by-step explanation:
<u>Simplfy in Algebra
</u>
We have the following expression
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Simplifying like factors in the denominator and numerator
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All the factors are perfect squares except
, thus we rewrite:
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Taking the square root of all the perfect square factors:
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