Please help me. Study island is hard

Answer:

x1= -2

x2= 6

Step-by-step explanation:

x^2-4x-12=0

x^2+2x-6x-12=0

x(x+2)-6(x+2)

(x+2)*(x-6)

one solution

x+2=0

x=-2

other solution

x-6=0

x=6

Answer:

56

Step-by-step explanation:

To find the "consequent," write out and solve an equation of ratios:

  3         x

------- = ------

  8         21

Through cross-multiplication, this yields  8x = 63, so that x must be x = 63/8.

Alternatively, solve this modified version of the original equation for x:

  3         21

------- = ------

  8          x

Then 3x = 8(21), or x = 8(7), or x = 56.

Note that 21 and 56 are in the ratio 3:8

Answer:

x = 60°

Step-by-step explanation:

∠ CGE = ∠ FGD = 30° ( vertical angles )

∠ CGB = 90° , then

x + 30° = 90° ( subtract 30° from both sides )

x = 60°

Answer:

A

Step-by-step explanation:

Desnity: mass/volume

3/20= .15

Step-by-step explanation:

AAA are the correct answer.

It is related to congurency.

Answer:

AAA

Step-by-step explanation:

You have 2 of angles. Add them together and subtract them by 180. That is how to got AAA.

Answer:

A = (1/2 x b x h ) 4 + l^2

= 1/2 x 5 x 8 x4 + 5 x 5

80 + 25

= D. 105 cm2

Answer:

105

Step-by-step explanation:

Answer:

Step-by-step explanation:

You can't see the picture really well

Answer: it b y’all

Step-by-step explanation: I took the test

Answer:

B

Step-by-step explanation:

To determine the maxima and minima of the polynomial, differentiate the given based on x and equate to 0.                                   C(x) = 400x - 0.2x²                               dC(x) / dt = 400 - 0.4 x = 0 The value of x is 1000. This is the value of the maxima. As the value of C(x) continously becomes lesser as the value of x is set higher, the minima is not identified. Substitute x to the original equation,                               C(x) = (400)(1000) - 0.2(1000²) = $ 200,000Thus, the answer is letter B. 

Answer:

ans: 31°

Step-by-step explanation:

<EFG = <EFH + <HFG

2x+52= 21 + ( x+31)

2x-x= 21 +31 -52

x= 0

so our question is to find <HFG so,

x+31°= 31°

Answer:

I think it is the first one i think

Step-by-step explanation:

Answer:

-6 and 11

Step-by-step explanation:

The only factors of 66 are 11, 6, 2 and 3

11*6 is the only pair whose product is 66

The difference betwen 11 and 6 is 5

11 must be positive and 6 negative since the sum is positve

3m^2 +5m-2-2m+18

3m^2 +3m+16

Answer:

3m² + 3 m + 16

Step-by-step explanation:

( 3 m ² + 5 m - 2 ) + ( - 2m + 18 )

Remove the unnecessary parantheses and rewrite

3 m ² + 5 m - 2 - 2 m + 18

combine like terms

3m² + 5 m - 2 m + 18 - 2

calculate the sum

3m² + 3 m + 16

Answer: 237,500 total decrease

Step-by-step explanation:

Answer:

I think it is 4

I am not sure about it

Answer:

The answer is25th August

Answer:

B.

Step-by-step explanation:

28 is not a multiple of 13.

Answer:

B

Step-by-step explanation:

2+5/2 is hard to add since first you have to make 2 into a fraction with the denominator 2. If you use the associative property, you can just easily combine -1/2 and 5/2 without any converting into fractions

Answer:

5x+8

Step-by-step explanation:

Answer:5x+8

Step-by-step explanation:

8x+13

-3x

5x+13

-5

5x+8

Answer:

D

Step-by-step explanation:

To check this answer, you could obviously graph the points, but without graphing, you can tell the line would be straight because each x value is multiplied by the same number to get the corresponding y value.

3 x 5 = 15, 4 x 5 = 20, etc. This shows linear growth. If each x value were multiplied by twice itself (3 x 6, 4 x 8, and so on), you wouldn't have a straight line because the number that x is multiplied by changes depending on the value of x.

Answer:

In order to make the maximum profit, the company should sell each widget at (the currency isn't given, so I'll be assuming USD) $36.

Step-by-step explanation:

The amount of profit y made by the company from selling each widget at x price is modeled by the equation:

[tex]y=-x^2+72x-458[/tex]

Since this is a quadratic with a negative leading coefficient, its maximum will occur at its vertex point. We want to find the price that the widget should be sold to make the maximum profit. So, we want to find the x-coordinate of the vertex. This is given by the formula:

[tex]\displaystyle x=-\frac{b}{2a}[/tex]

In this case, a = -1, b = 72, and c = -458. Substitute and evaluate:

[tex]\displaystyle x=-\frac{72}{2(-1)}=36[/tex]

In order to make the maximum profit, the company should sell each widget at (the currency isn't given, so I'll be assuming USD) $36.

Answer:

33

Step-by-step explanation:

The formula for solving the area of a Trapezoid is a+b/2*h if we substitute the value to 16+3/2*3 it will equal 33

Answer:

This doesn't make sense because there is no C variable, but I will solve for f if that helps.

Step-by-step explanation:

[tex]f=1.80+32[/tex]

       [tex]-32[/tex]   [tex]-32[/tex]          

[tex]f=-30.2[/tex]      

Answer:

11  1.6

12  Mauricio

Step-by-step explanation:

11.  Take the absolute value of each number to determine which is furthest from zero

|-1.5| and |1.6|

1.5  and 1.6

1.6 is greater than 1.6  so it is further from 0

12.  The fastest time is the smallest time

The ones place all has 7's so look at the tenths place

The smallest number will have the fastest time

Mauricio has a 2 which is the smallest number

Mauricio has the fastest time

Answer:

La población 20 horas después será de 321,161 bacterias.

Step-by-step explanation:

t horas después de iniciar la observación, tiene una razón de cambio de P'(t) = 350 e0.18t + 220 e-0.3t.

Esto implica que la población después de t horas viene dada por:

[tex]P(t) = \int P^{\prime}(t) dt[/tex]

[tex]P(t) = \int (350e^{0.18t} + 220e^{-0.3t}) dt[/tex]

Teniendo en cuenta que

[tex]\int e^{at} dt = \frac{1}{a}e^{at}[/tex]

[tex]P(t) = \int (350e^{0.18t} + 220e^{-0.3t}) dt[/tex]

[tex]P(t) = \frac{350}{0.18}e^{0.18t} - \frac{220}{0.3}e^{-0.3t} + K[/tex]

En que k es la población inicial, o sea, [tex]K = 250000[/tex]. Entonces

[tex]P(t) = 1944.44e^{0.18t} -733.33e^{-0.3t} + 250000[/tex]

¿Cuál será la población 20 horas después?

Esto eres P(20). Entonces:

[tex]P(20) = 1944.44e^{0.18*20} -733.33e^{-0.3*20} + 250000 = 321161[/tex]

La población 20 horas después será de 321,161 bacterias.

Answer:

(x+1)² = 14

a = 1, b = 14

Step-by-step explanation:

Given the equation, x² + 2x = 13

We are to use the completing the square method to express in the form

(x + a)² = b

x² + 2x = 13

Add the square of half of the coefficient of x to both sides

Coefficient of x = 2

Half of the coefficient of x = 2/2

Square of the result = (2/2)²

Square of the result = 1²

Add (1/2)² to both sides

x² + 2x + (1)² = 13 + (1)²

(x+1)² = 13 + 1

(x+1)² = 14

Compare with  (x+a)² = b

a = 1 and b = 14

9x²-24xy+16y²

(3x)²-2.(3x)(4y) +(4y)²

(3x-4y)²

(3x-4y)(3x-4y)

Answer:

[tex](3x -4y)^2[/tex]

Step-by-step explanation:

[tex]9x^2 - 24xy + 16y^2 = (3x)^2 - 24xy + (4y)^2[/tex]

                           [tex]=(3x)^2 -2(3x \times 4y) + (4y)^2\\[/tex]

a = 3x , b = 4y . The expression [tex]a^2 - 2ab + b^2 = (a-b)(a-b) =(a-b)^2[/tex]

                           [tex]=(3x -4y)(3x - 4y)[/tex]

[tex]9x^2 - 24xy + 16y^2 = (3x -4y)^2[/tex]

Step-by-step explanation:

a) 2z+3z+4z=180

9z=180

z=20

So,three angles are 40,60 and 80

b) (y+30)+(2y+80)+(y+10)=180

y+30+2y+80+y+10=180

4y+120=180

4y=60

y=15

Three angles are 45,110,25