<h3>
Answer: cos(76)</h3>
=========================================================
Explanation:
The original expression is of the pattern cos cos + sin sin. This pattern matches the second identity in the hint. Specifically, we'll say the following:
cos(A - B) = cos(A)cos(B) + sin(A)sin(B)
cos(A)cos(B) + sin(A)sin(B) = cos(A - B)
cos(94)cos(18) + sin(94)sin(18) = cos(94 - 18)
cos(94)cos(18) + sin(94)sin(18) = cos(76)
----------
We can verify this by use of a calculator. Make sure your calculator is in degree mode.
- cos(94)cos(18) + sin(94)sin(18) = 0.24192
- cos(76) = 0.24192
Both expressions give the same decimal approximation, so this helps confirm the two expressions are equal. You could also use the idea that if x = y, then x-y = 0. Through this method, you'll subtract the left and right hand sides and you should get (very close to) zero.
Answer:
74.0°
Step-by-step explanation:
In triangle JKL, k = 4.1 cm, j = 3.8 cm and ∠J=63°. Find all possible values of angle K, to the nearest 10th of a degree
Solution:
A triangle is a polygon with three sides and three angles. Types of triangles are right angled triangle, scalene triangle, equilateral triangle and isosceles triangle.
Given a triangle with angles A, B, C and the corresponding sides opposite to the angles as a, b, c. Sine rule states that for the triangle, the following holds:

In triangle JKL, k=4.1 cm, j=3.8 cm and angle J=63°.
Using sine rule, we can find ∠K:

Answer: x = 10 y=20
Step-by-step explanation:
You can answer this question by plugging in each equation:
2x=y, x+y=30. Let us plug y as 2x in the second equation x+y=30
x+2x= 30
3x= 30
x=10
After we found x we can then find y by plugging the 10 for x.
2(10) = y
y =20
or you could plug in the other equation
10+y=30
subtract 10 from 30 and we get 20
to double check we can plug in both numbers
2(10) = 20 which is correct
and 10 + 20 = 30 which is correct