Answer:
steps below
Step-by-step explanation:
Are you going to solve the value of A or just a proof the equation
cos 2A = cos² A - sin² A
2cos²A-cos2A-1 = 2cos²A - (cos² A - sin² A) - 1 = cos² A + sin² A - 1
2cos²A-cos2A-1 = 1 - 1 = 0
A: 90° or 270° or 450° .....
Answer:
30% of her writing utensils are pencils.
Step-by-step explanation:
We can get this by dividing the number of pencils by the total number of utensils.
6/20 = .3 = 30%
The area of the David's pantry = 10 square feet.
The length of the pantry = 5 feet.
<h3>Define the term area of the rectangle?</h3>
- The territory inhabited by a rectangle inside its 4 sides or limits is known as its area.
- The area of such a rectangle is determined by its sides. Essentially, the formula calculating area is equivalent to the product of the rectangle's length and breadth.
For the given question.
- David's kitchen is 60 square feet in size.
- The kitchen is six times the size of the living room.
Thus,
Area of kitchen = 6 x area of the pantry
60 = 6 x area of the pantry
area of the pantry = 60 / 6 = 10 square feet.
Area of the pantry = length x breadth
10 = length x 2
length = 10/2 = 5 feet.
Thus, the length of the pantry is found as the 5 feet.
To know more about the area of the rectangle, here
brainly.com/question/16239445
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10, 20 , 30, 45 has 5 as their greatest common factor
Answer:
A Variable
Step-by-step explanation:
Variables are used to mark an unknown value. Common math problems ask you to solve for it.
For example in 5x+23=45, 'x' is the variable.
A constant is a number without a variable.
<em>Brainilest Appreciated. </em>