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:

2.

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:
Number of edges in the resulting solid = 12
Step-by-step explanation:
A wooden block measures 2 inches by 2 inches by 3 inches. A wedge is cut off from each corner of the block by slicing at points that are 1 inch from each corner.
We are supposed to find the number of edges that are in the resulting solid.
In some corners , if we take out inch from both, then there would be nothing remaining.
The two faces along the height would be removed and it will become sharpened.
So the number of edges = 4 + 4 + 4 = 12
Given BD and AC is a diameter of the circle:
We need to find the following:
1. measure of the arc BA
So,
the measure of the minor arc BA = 44
The measure of the major arc BA = 360 - 44 = 316
2. the measure of the arc ACB = 360 - 44 = 316
3. The arc BCD is a semicircle of the circle
So, the measure of the arc BCD = 180
Answer: 5
Step-by-step explanation:
use formula a^2 + b^2 = c^2
a^2 + 12^2 = 13^2
a^2 + 144 = 169
- 144 -144
a^2 = 25
sqrt sqrt
a = sqrt (25)
a = 5