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:
b
Step-by-step explanation:
b
Answer:
6 pencils each
Step-by-step explanation:
2 dozen = 24
24/4 = 6
<h3>The true statement about circumference of a circle is: circumference is found by multiplying Pi by the diameter</h3>
<em><u>Solution:</u></em>
<em><u>The circumference of a circle is given as:</u></em>

Where,
"r" is the radius of circle
We know that,

<em><u>Thus the circumference can also written as:</u></em>

Thus, the circumference is found by multiplying Pi by the diameter is correct statement
Answer: well the answer is 9
Step-by-step explanation: