Answer:
B) 81π units²
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Geometry</u>
Radius of a Circle Formula: r = d/2
Area of a Circle Formula: A = πr²
Step-by-step explanation:
<u>Step 1: Define</u>
Diameter <em>d</em> = 18 units
<u>Step 2: Manipulate Variables</u>
Radius <em>r</em> = 18 units/2 = 9 units
<u>Step 3: Find Area</u>
- Substitute in <em>r</em> [Area of a Circle Formula]: A = π(9 units)²
- [Area] Evaluate exponents: A = π(81 units²)
- [Area] Multiply: A = 81π units²
5
the factors of 20 are 1, 2, 4, 5, 10, 20
the factors of 15 are 1, 3, 5, 15
the common factor of 20 and 15 is 5
Answer:
z =
Explanation:
Inside angles equal to 120
Angles on a straight angel equal to 180
180 - 120 = 69
A=1/2 b*h
So substitute it in 1/2*1/2*4
1/2*1/2= 1/4
1/4*4= 4/4= 1 so the entrance is 1 foot tall
A=adult
c=children
total lumber=30
total number=adults+children
a+c=30
total cost=50
total cost=acost+ccost
acost=a times cost per adult=a times 3=3a
ccost=c times cost per child=c tiems 1=1c=c
total cost=3a+c
50=3a+c
equiaotn are
a+c=30
3a+c=50
multiplyu first by -1 and add
3a-a+c-c=50-30
2a=20
a=10
sub
10+c=30
c=20
answer is A