Answer:
x=3.4
y=-6.75
Step-by-step explanation:
5x+4y=-10 (equation 1 )
-5x+3y=-17 (equation 2)
7y=-27
y=-6.75
substitution (equation 1 ) y=-6.75
5x-27=-10
5x=17
x=3.4
Answer:
42 square inches
Step-by-step explanation:
Area of a triangle = (1/2)(base)(height)
A = 1/2(12)(7)
A = 1/2(84)
A = 42
Answer: 3 meters downward per second
Step-by-step explanation:
If it moved downward 15 meters for every 5 seconds and to find the change in the elevation each second then divide the meters by 5.
15/5 = 3
3 meters per second
Answer:
Step-by-step explanation:
Multiply the equation by 4
5x - 2 + 2 = 2*(3y + 2)
5x +0 = 2*3y + 2*2
5x = 6y + 4
5x - 6y = 4 --------------------(I)
Multiply the equation by 6
2*(7y + 3) = 3x + 2*7
14y + 6 = 3x + 14
14y = 3x + 14 - 6
14y = 3x + 8
-3x + 14y = 8 ------------------------(II)
Multiply equation (I) by 3 and equation (II) by 5 and then add
(I)*3 15x - 18y = 12
(II)*5 <u>-15x + 70y = 40</u> {Now add}
52y = 52
y = 52/52
y = 1
Substitute y =1 in equation (I)
5x - 6*1 = 4
5x - 6 = 4
5x = 4 +6
5x = 10
x = 10/5
x = 2
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
