please answer this!!​

Answer:

A ≈ 21.22 m²

Step-by-step explanation:

The area (A) of a triangle using Heron's formula is

A = [tex]\sqrt{s(s-a)(s-b)(s-c)}[/tex]

where s is the semi perimeter and a, b, c the sides of the triangle.

Here the perimeter of the equilateral triangle is 21 m , then

a = b = c = 21 ÷ 3 = 7 m

s = 21 ÷ 2 = 10.5

Then

A = [tex]\sqrt{10.5(10.5-7)(10.5-7)(10.5-7)}[/tex]

   = [tex]\sqrt{10.5(3.5)(3.5)(3.5)}[/tex]

   = [tex]\sqrt{450.1875}[/tex]

   ≈ 21.22 m² ( to 2 dec. places )

Answer:

D

Step-by-step explanation:

(the above graph depicts a horizontal line that intersects the y axis at -2)

(so, y = -2)

Answer:

0

Step-by-step explanation:

Horizontal line x axis is 0 while the vertical y axis is undefined.

Answer:

x = ±1/2

Step-by-step explanation:

x^2-1/4=0

Add 1/4 to each side

x^2 -1/4+1/4 = 0+1/4

x^2 = 1/4

Take the square root of each side

sqrt(x^2) = sqrt(1/4)

x = ±1/2

Answer:

126

Step-by-step explanation:

Answer:

126°

Step-by-step explanation:

x = (87+165)/2

x = 252/2

x = 126

Answered by GAUTHMATH

Step-by-step explanation:

Find the slope of AB

: The slope is

[tex] \frac{7 - 0}{3 - 8} = - \frac{7}{5} [/tex]

Find the y intercept by plugging coordinates in

[tex]0 = - \frac{ 7}{5} (8) + b[/tex]

[tex]0 = \frac{ - 56}{5} + b[/tex]

[tex]b = \frac{56}{5} [/tex]

Find CD: We know that AB and CD are parallel to each other so this means they both have the same slope.

We can find the next point by subtracting 7 from the y coordinate of Point D, Adding 5 to the x coordinate of Point D.

Point C=(10,-2).

Find the y intercept by a plugging coordinates in

[tex] 5 = - \frac{7}{5} (5) + b[/tex]

[tex]5 = - 7 + b[/tex]

[tex]12 = b[/tex]

So the Equation of Line CD is

[tex] - \frac{7}{5} x + 12[/tex]

Answer:  g(x) = (1/16)*x^2

========================================================

Explanation:

Plug x = 4 into f(x) to find that f(4) = 16.

The output y = 16 drops to y = 1. We've multiplied by 1/16 to get this to happen.

In other words,

g(x) = (1/16)*f(x)

g(4) = (1/16)*f(4)

g(4) = (1/16)*16

g(4) = 1

So we can say that,

g(x) = (1/16)*f(x)

g(x) = (1/16)*x^2

and furthermore, we can say f(x) has been vertically compressed by a factor of 16.

Answer:

180 km

Step-by-step explanation:

1 cm=12 km

15 cm=12×15=180 km

Answer:

X=15 since it the same

Step-by-step explanation:

X is simply equal to 15 because it an equilateral triangle

Answer:

50%

Step-by-step explanation:

There are 8 professors. 4 of them are younger than 47 (not equal to 47, YOUNGER)

1. 42

2. 34

3. 44

4. 36

To find percentage we have to do 4/8 x 100

this equals to 50%

Answer:

Hence the critical value for the right-tailed test is [tex]F_{15,23,0.05}=2.1282[/tex]. Since the test value is greater than the critical value so we reject the null hypothesis.

Step-by-step explanation:  

Hypotheses are:

[tex]H_{0}:\sigma_{1}^{2}=\sigma_{2}^{2}\\H_{a}:\sigma_{1}^{2}>\sigma_{2}^{2}[/tex]

Here we have s_{1}=6800 and s_{2}=3900. Here we will use F -test. The Value of test statistics is  

[tex]F=\frac{s_{1}^{2}}{s_{2}^{2}}\\\\F=\frac{6800^{2}}{3900^{2}}\\\\F=3.0401[/tex]  

Here the degree of freedom of the numerator is [tex]df_{1}=n_{1}-1=16-1=15[/tex] and The degree of the denominator is

[tex]df_{2}=n_{2}-1 \\\\=24-1=23 .[/tex]

The critical value for the right-tailed test is [tex]F_{15,23,0.05}=2.1282[/tex]. Since the test value is greater than the critical value so we reject the null hypothesis.  

Answer:

Step-by-step explanation:

Answer:

x> 0

Step-by-step explanation:

There is an open circle at 0 so this means it is not equal to

The line goes to the right so x is greater than

x> 0

Answer:

14, 21

Step-by-step explanation:

LCM : least common multiplier.

x + y = 35

LCM = 42

means that there is a combination of 2 of the following divisors of 42 :

2, 3, 6, 7, 14, 21

so, which two of these numbers can create the sum of 35 ?

only 14 and 21

Answer:

The y-intercepts of the two lines will represent the cost per megabyte of data used in each plan.

Step-by-step explanation:

i also took the test

Answer:

The y intercept forms the two lines.

Step-by-step explanation:

I just took the test

Answer:

When a transversal intersects with two parallel lines eight angles are produced. The eight angles will together form four pairs of corresponding angles.

Answer:

I know but I will not tell you have to do by self

Answer:

4y4 the 1st one

may this help you

Answer:

16-28+3 do it now ok!!!!!!

Answer:

If b=4,

b^2-7b+3

=4^2-7(4)+3

=16-28+3

=-9

Answer:

G' (-2,-1) F' (-5,0) E' (-4,3)

Step-by-step explanation:

This is because R90(x,y)=(-y,x)

G(-1,2)=G'(-2,-1)

F(0,5)=F'(-5,0)

E(3,4)= E'(-4,3)

Answer:

30-60-90

Step-by-step explanation:

A 30-60-90 triangle is a right angled triangle

Please mark it as brainliest if it helped

Answered by Gauthmath

Answer:

A (30 - 60 - 90) right triangle has the side ratios: [tex]x, x\sqrt{3}, 2x[/tex].

Step-by-step explanation:

A right triangle with the angle measures (30 - 60 - 90) is often referred to as a special right triangle becaase its sides follow the following ratio,

The side;                                                          Angle it's opposite to;

[tex]x[/tex]                                                                        30

[tex]x\sqrt{3}[/tex]                                                                   60

[tex]2x[/tex]                                                                      90

Answer:

    3631.681108 ft^2

Step-by-step explanation:

The surface area of a cylinder is

SA = 2pi r^2 + 2pi r h  where r is the radius and h is the height

    = 2pi (17)^2  + 2 pi (17)(17)

    = 578pi +578pi

    = 1156pi

Approximate pi with the pi button

    3631.681108 ft^2

Answer:

x=5

Step-by-step explanation:

Since both of these length are equal, 6x+4=8x-6, 2x=10, x=5

Answer:

There are no like terms

Step-by-step explanation:

×^2+9

=ײ+9

Answer:

8

Step-by-step explanation:

x = centesimal angle (100 degrees in a right angle)

y = sexagesimal angle (90 degrees in a right angle)

x - y = 15

x×90/100 = y

x×9/10 = y

x - x×9/10 = 15

10x/10 - 9x/10 = 15

x/10 = 15

x = 150

y = 150×9/10 = 15×9 = 135

using centesimal system :

the sum of all external angles in a polygon is 400 degrees (a full circle).

one external angle is the complement of one internal angle to 200 degrees = 200-150=50 degrees.

to find the number of sides of the polygon we need to find the number of angles or corners. and that is how many external angles fit into the full circle.

n = 400/50 = 8

the polygon has 8 sides

Answer:

3560 people.

Step-by-step explanation:

You have to do 89% × 4000.

Or 0.89×4000=3560.

So 3560 is the answer.

Answer:

angle BAD= angle BCD = 100

then,

angle BCD + angle ECD = 180

100+ angle ECD = 180

angle ECD= 180-100 = 80

angle ECD =80

Answer:

d, 64.26 e, 27.475 f, 126.14

Step-by-step explanation:

For d, the diameter is 12 and the equation to find the circle is πr2. 6 is the radius, so 6x6=36, and 36x3.14 cause π=3.14. 36x3.14=113.04, and we have to divide by 2 cause its only half of the circle is shaded. 113.04/2=56.52. Now we have to do 12x12 to find the whole area of the square which is 144, then 144-113.04 cause we are finding the shade outside of the circle, so 144-113.04=30.96. Finally we divide by four of the outside corners, so 30.96/4=7.74. 7.74+56.52=64.26

So D is 64.26

WARNING: The rest of them i'm not gonna explain much of it i'm just gonna say what to do, but i'll put the answers! they are all very similiar. Also, i might be wrong, so if i'm wrong i'm sorry, i'm learning too!

For E, we have to find the smaller circle that has diameter of 10, then the bigger circle is diameter of 15, so find the area of the bigger circle then minus the smaller circle than divide by 2.

78.5-23.55=54.95

54.95/2=27.475

for F, we have to find the area of the half circle with diameter of 14, so find the area of the whole circle, and we dont have to divide two cause we have the other half on the other half, and half plus a half is a whole. Then we have to do 20x14 to find the whole square minus the circle.

280-153.86=126.14

Remember this might be wrong, so sorry if it is

Answer:

36; 18; -35; 0

Step-by-step explanation:

They break even again when their profit is zero, i.e. at the x-intercept (36).

The worst case scenario is when their profit is the lowest, i.e. at the minimum vertex where they produce 18 items for a profit (in this case loss) of -35 dollars.

The first root tells us that the profit will be zero when zero products are produced.