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3 years ago

MEGA POINTS... CAN CHAT AFTERWARDS...

Mathematics

1 answer:

slega [8]3 years ago

8 0

Answer:

Step-by-step explanation:

Given

x² - 18x + --- = 4 + ----

To complete the square

add ( half the coefficient of the x- term )² to both sides

x² + 2(- 9)x + 81 = 4 + 81

(x - 9)² = 85 ( take the square root of both sides )

x - 9 = ± $\sqrt{85}$ ( add 9 to both sides )

x = 9 ± $\sqrt{85}$ ← exact solutions

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A retailer who sells backpacks estimates that by selling them for x dollars each, she will be able to sell 100−x backpacks each

zvonat [6]

Answer:

x = 50

R = $2500

Step-by-step explanation:

Given in the question a quadratic equation,

−x² + 100x

To find the selling price, x, which will give highest revenue, y, we will find maximum value of parabola curve −x² + 100x

The value of -b/2a tells you the value x of the vertex of the function

−x² + 100x

here a = -1

b = 100

Selling price = -(100)/2(-1)

= 50

R = −(50)² + 100(50)

= 2500

8 0

4 years ago

Micah places a mirror on the ground 24 feet from the base of a tree. He walks

irina [24]

The height of tree is 8 feet

<h3><u>Solution:</u></h3>

Given, Micah places a mirror on the ground 24 feet from the base of a tree

At that point, Micah's eyes are 6 feet above the ground

And he is 9 feet from the image in the mirror.

To find : height of tree = ?

Let "n" be the height of tree

From the question, we can see there is a directly proportional relationship between heights and distances.

Proportional relationships are relationships between two variables where their ratios are equivalent.

$\frac{\text { height of micah eyes above ground }}{\text { distance of micah from mirror }}=\frac{\text { height of tree above the ground }}{\text { distance of tree from mirror }}$

$\begin{array}{l}{\frac{6 \text { feet }}{9 \text { feet }}=\frac{n \text { feet }}{24 \text { feet }}} \\\\ {\frac{6}{9}=\frac{n}{24}} \\\\ {\text { n }=\frac{1}{3} \times 24} \\\\ {\text { n }=8}\end{array}$

Hence, the height of the tree is 8 feet

6 0

3 years ago

A cylinder has a radius of 3 cm. Sand is poured into the cylinder to form a layer 2 cm deep. What is the volume of sand in the c

netineya [11]

Answer:

Volume=56.54cm³

Step-by-step explanation:

$Solution,\\\\Radius(r)=3cm\\\\Height(h)=2cm\\\\Now,\\\\Volume=\pi r^{2} h\\\\Volume=\pi *(3cm)^{2} *2cm\\\\Volume=18\pi cm^{3} =56.54cm^{3}$

3 0

2 years ago

Which of these triangle pairs can be mapped to each other using a reflection

tia_tia [17]

Help me! I’ll mark you brainly!

8 0

3 years ago

(5x + 7)(5x – 7)<br> Foil method

Pavlova-9 [17]

Answer:

25x-49

Step-by-step explanation:

5x×5x=25x 5x×-7= -35x

7×5x=35x 7×-7=-49

(combine like terms)25x+-35x+35x= 25

hope that helped you!

6 0

3 years ago