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3 years ago

The diameter of a circle is 20 feet. Using the formula A = r2, what is the area of the circle? Use 3.14 for pi.

Mathematics

1 answer:

sergey [27]3 years ago

3 0

Area = PI * radius ^ 2
radius = 10 feet
Area = PI * 100
Area = 3.14 * 100
Area = 314 square feet

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Twenty-four apple trees produced 220 lbs of apples. At the same rate, how many trees are needed to produce 550 lbs of apples?

defon

Answer:

Step-by-step explanation:

220*2 = 440

+ 220/2 = 550

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3 years ago

A parabola can be drawn given a focus of (6,-1) and a directrix of y = 9. What can be said about the parabola?

zavuch27 [327]

Answer:

Since the focus is at (-6,-11) and the directrix is at y=9:

The vertex is halfway between the focus and the directrix, so the vertex is at (-6,-1). (Draw this on graph paper if that doesn't make sense.)

The general form (conics form) of a parabola: 4p(y-k)=(x-h)^2 (vertex is (h,k) and "p" is the distance between the focus and vertex (or between vertex and directrix)).

(h,k) = (-6,-1)

p = 10 (distance between focus and vertex), so 4p = 40.

Therefore:

40(y+1)=(x+6)^2

Or if you need to rearrange to "vertex form": y=(1/40)(x+6)^2 - 1

Step-by-step explanation:

3 0

3 years ago

What is the sum of -2.16 and -1.75

Andreyy89

-3. 91 is the sum of -2.16 and -1.75

5 0

3 years ago

Read 2 more answers

What is this answer

Radda [10]

use the distance formula

$\sqrt{(x2-w1)^{2} +(y2-y1) ^{2} }$

You ll need to do it t times:

x1 y1 x2 y2

(-1, 5) (4, 2) = (-1, 5) (4, 2)

(4, 2) (0,0)

(0,0) (5,5)

(5,5) (-1, 5)

then add all your results

4 0

3 years ago

Which is the equation of the line that passes through the points (4,3) and (6,2)?

NeX [460]

Answer:

$\large \boxed{y = - 0.5x + 5}$

Step-by-step explanation:

Goal

Find the equation of the line.

Given

Coordinate points which are (4,3) and (6,2).

Step 1

Find the slope by using slope formula or rise over run.

$\large{m = \frac{y_2-y_1}{x_2-x_1} }$

Substitute the coordinate points in

$m = \frac{3 - 2}{4 - 6} \\ m = \frac{1}{ - 2} \\ m = - \frac{1}{2} \longrightarrow - 0.5 \\ m = - 0.5$

Step 2

Rewrite the equation in slope-intercept form by substituting m = -0.5

$\large{y = mx + b}$

Substitute m = -0.5

$y = - 0.5x + b$

Step 3

Find the value of b by substituting any given coordinate points in the equation.

Substituting both coordinate points still give the same answer.

Step 3.1

Substitute (4,3) in the equation.

$y = - 0.5x + b \\ 3 = - 0.5(4) + b \\ 3 = - 2.0 + b \\ 3 = - 2 + b \\ 3 + 2 = b \\ 5 = b$

Step 3.2

Substitute (6,2) in the equation.

$y = - 0.5 x+ b \\ 2 = - 0.5(6) + b \\ 2 = - 3.0 + b \\ 2 = - 3 + b \\ 2 + 3 = b \\ 5 = b$

Step 4

Rewrite the equation again by substituting the value of b.

$y = - 0.5x + b$

Substitute b = 5 in the equation.

$y = - 0.5x + 5$

Hence, the equation is y = -0.5x + 5

3 0

3 years ago