65% of 186 Please show work! (my teacher needs me to show work)

573 dividing 3 deciding were to start dividing

vaieri [72.5K]

??????? That Doesn't Make Sense

6 0

3 years ago

What's the area of a circle with diameter 18 units? Question 8 options: A) 9π units2 B) 81π units2 C) π units2 D) 18π units2

Anna [14]

Answer:

B) 81π units²

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Geometry

Radius of a Circle Formula: r = d/2

r is radius
d is diameter

Area of a Circle Formula: A = πr²

Step-by-step explanation:

Step 1: Define

Diameter d = 18 units

Step 2: Manipulate Variables

Radius r = 18 units/2 = 9 units

Step 3: Find Area

Substitute in r [Area of a Circle Formula]: A = π(9 units)²
[Area] Evaluate exponents: A = π(81 units²)
[Area] Multiply: A = 81π units²

6 0

3 years ago

Find the standard equation of a sphere that has diameter with the end points given below. (3,-2,4) (7,12,4)

DiKsa [7]

Answer:

The standard equation of the sphere is $(x-5)^{2} + (y-5)^{2} + (z-4)^{2} = 53$

Step-by-step explanation:

From the question, the end point are (3,-2,4) and (7,12,4)

Since we know the end points of the diameter, we can determine the center (midpoint of the two end points) of the sphere.

The midpoint can be calculated thus

Midpoint = $(\frac{x_{1} + x_{2} }{2}, \frac{y_{1} + y_{2} }{2}, \frac{z_{1} + z_{2} }{2})$

Let the first endpoint be represented as $(x_{1}, y_{1}, z_{1})$ and the second endpoint be $(x_{2}, y_{2}, z_{2})$ .

Hence,

Midpoint = $(\frac{x_{1} + x_{2} }{2}, \frac{y_{1} + y_{2} }{2}, \frac{z_{1} + z_{2} }{2})$

Midpoint = $(\frac{3 + 7 }{2}, \frac{-2+12 }{2}, \frac{4 + 4 }{2})$

Midpoint = $(\frac{10 }{2}, \frac{10}{2}, \frac{8 }{2})\\$

Midpoint = $(5, 5, 4)$

This is the center of the sphere.

Now, we will determine the distance (diameter) of the sphere

The distance is given by

$d = \sqrt{(x_{2} - x_{1})^{2} +(y_{2} - y_{1})^{2} + (z_{2}- z_{1})^{2} }$

$d = \sqrt{(7 - 3)^{2} +(12 - -2)^{2} + (4- 4)^{2}$

$d = \sqrt{(4)^{2} +(14)^{2} + (0)^{2}$

$d = \sqrt{16 +196 + 0$

$d =\sqrt{212}$

$d = 2\sqrt{53}$

This is the diameter

To find the radius, r

From $Radius = \frac{Diameter}{2}$

$Radius = \frac{2\sqrt{53} }{2}$

∴ $Radius = \sqrt{53}$

r = $\sqrt{53}$

Now, we can write the standard equation of the sphere since we know the center and the radius

Center of the sphere is $(5, 5, 4)$

Radius of the sphere is $\sqrt{53}$

The equation of a sphere of radius r and center $(h,k,l)$ is given by

$(x-h)^{2} + (y-k)^{2} + (z-l)^{2} = r^{2}$

Hence, the equation of the sphere of radius $\sqrt{53}$ and center $(5, 5, 4)$ is

$(x-5)^{2} + (y-5)^{2} + (z-4)^{2} = \sqrt{(53} )^{2}$

$(x-5)^{2} + (y-5)^{2} + (z-4)^{2} = 53$

This is the standard equation of the sphere

6 0

3 years ago

Subtract and reduce: 2 2/3 - 1 1/2

babunello [35]

Step-by-step explanation:

I used a calculator but the answer is 1 1/6

5 0

3 years ago

Please answer quickly! A recipe asks for 1/3 cup of nuts. How many nuts are needed to make 1/4 of the recipe?

anastassius [24]

Answer: 1/12 of a cup

To get this answer, you multiply 1/4 by 1/3
Multiply straight across
(1/4)*(1/3) = (1*1)/(4*3) = 1/12

6 0

3 years ago