What is the area of this?

Find all solutions to x³+3x² − 9x − 27 = 0 by factoring the equation.

SCORPION-xisa [38]

Answer:

The solutions are $x=-3,\:x=3$

Step-by-step explanation:

To factor this cubic polynomial $x^3+3x^2-9x-27$ you must:

Group the polynomial into two sections

$x^3+3x^2-9x-27=\left(x^3+3x^2\right)+\left(-9x-27\right)$

Factor out -9 from $(-9x-27)$

$(-9x-27)=-9\left(x+3\right)$

Factor out $x^2$ from $(x^3+3x^2)$

$(x^3+3x^2)=x^2\left(x+3\right)$

$x^3+3x^2-9x-27=-9\left(x+3\right)+x^2\left(x+3\right)$

Factor out common term $x+3$

$-9\left(x+3\right)+x^2\left(x+3\right)=\left(x+3\right)\left(x^2-9\right)$

$x^3+3x^2-9x-27=\left(x+3\right)\left(x^2-9\right)$

Factor $x^2-9$

$x^2-9=\left(x+3\right)\left(x-3\right)$

$x^3+3x^2-9x-27= \left(x+3\right)\left(x+3\right)\left(x-3\right)$

$x^3+3x^2-9x-27=\left(x+3\right)^2\left(x-3\right)=0$

Using the Zero Factor Theorem: = 0 if and only if = 0 or = 0

$x+3=0, \quad{x=-3}\\x-3=0, \quad{x=3}$

The solutions are

$x=-3,\:x=3$

3 0

2 years ago

How is simplifying similar to division?

Alex

When you simpilfy a fraction you make it smaller. When you divide a number you make it smaller.

Ex: 5 /5 1
_ = _
10 /5 2

3 0

3 years ago

Read 2 more answers

A theme park had 1099 visitors in 3 days.There were twice as many visitors on saturday than on Friday.There were 234 more visito

Blababa [14]

Answer: there were 692 visitors on Saturday.

Step-by-step explanation:

Let x represent the number of visitors that were there on Friday.

Let y represent the number of visitors that were there on Saturday.

Let z represent the number of visitors that were there on Sunday.

The theme park had 1099 visitors in 3 days. It means that

x + y + z = 1099- - - - - - - - - - - - - -1

There were twice as many visitors on saturday than on Friday. This means that

y = 2x

x = y/2

There were 234 more visitors on Sunday than on Saturday. This means that

z = y + 234

Substituting x = y/2 and z = y + 234 into equation 1, it becomes

y/2 + y + y + 234 = 1099

Cross multiplying by 2, it becomes

y + 2y + 2y + 468 = 2198

5y = 2198 - 468

5y = 1730

x = 1730/5

x = 346

y = 2x = 2 × 346

y = 692

z = y + 234 = 692 + 234

z = 926

3 0

2 years ago

Solve the system of equations below. A. B. C. D.

timofeeve [1]

Answer:

A. (-7 -2)

Step-by-step explanation:

You can eliminate y by multiplying the first equation by 7 and subtracting 6 times the second equation:

7(-3x +6y) -6(5x +7y) = 7(9) -6(-49)

-21x +42y -30x -42y = 63 +294 . . . . eliminate parentheses

-51x = 357 . . . . . . . . collect terms

x = -7 . . . . . . . divide by -51. This matches answer choice A.

7 0

2 years ago

Please help me find the total area of the composite figure below (geometry)

Akimi4 [234]

Answer:

lw + $\frac{1}{2}$ × π × $(\frac{l}{2} )^{2}$ ⇒ Answer D is correct

Step-by-step explanation:

First, let us find the area of the semi-circle.

Area = $\frac{1}{2}$ × π × r²

Given that,

diameter of the semi-circle is ⇒ l

∴ radius ⇒ l / 2

Let us find it now.

Area = $\frac{1}{2}$ × π × r²

Area = $\frac{1}{2}$ × π × $(\frac{l}{2} )^{2}$

Secondly, let us find the area of the rectangle.

Area = length × width

Given that,

length ⇒ l

width ⇒ w

Let us find it now.

Area = length × width

Area = l ×w

Area = lw

And now let us find the total area.

Total area = Area of the rectangle + Area of the semi - circle

Tota area = lw + $\frac{1}{2}$ × π × $(\frac{l}{2} )^{2}$

8 0

2 years ago