the perimeter of equilateral triangle is 21m. Find the area. Using Heron's Formula


plzzz answer fast i will mark brainliest.

Answer:

Step-by-step explanation:

The basic 30-60-90 triangle ratio is:

Side opposite to 30° angle is : x

Side opposite to 60° angle is : x √3

Side opposite to 90° angle is : 2x

From the diagram we learn that

x√3 = 10

[tex]x = \frac{10}{\sqrt{3}}=\frac{10*\sqrt{3} }{\sqrt{3}*\sqrt{3}}\\\\x=\frac{10\sqrt{3}}{3}= 5.77\\[/tex]

∠T = 30°, Side opposite to ∠T is AC = 5.77

∠A = 90°, side opposite to ∠A is TC = 2x = 2*5.77 = 11.54

Step-by-step explanation:

gradient(m)=change in y/change in x

=5-1/-9-(-4)

=4/-9+4

=4/-5

equation now

y-y1=m(x-x1)

y-1=4/-5[x-(-4)]

y=4/-5(x+4)+1

y=-4/5x-16/5+1

y=-4/5x-21/5

Answer:

y = -4/5x - 11/5

Step-by-step explanation:

First, find the slope using the slope formula.

[tex]m=\frac{y_1-y_2}{x_1-x_2}\\\\m=\frac{1-5}{-4-(-9)}\\\\m=-\frac{4}{5}[/tex]

Then, use the point-slope formula and substitute the values for the variables. I'll use (-4, 1) in this instance.

[tex]y-y_1=m(x-x_1)\\\\y-1=-\frac{4}{5}(x+4)\\\\y-1=-\frac{4}{5}x-\frac{16}{5}\\\\y=-\frac{4}{5}x-\frac{11}{5}[/tex]

Answer: y=80/5x+80

Step-by-step explanation:

At one point graph goes from (0,400) to (25,800). So the y intercept is 400 because that’s where the line was at x=0. 0 to 25 is 25. 400 to 800 is 400. So the equation would be y=400/25x+400. But you can divide all of it by 5 to get y=80/5x+80.

Answer:

6 - 3x = 4 - X-3 - 2x

-3x+x+2x=4-6-3

0x=-5

No solutions

Answer:

70

Step-by-step explanation:

we have the angle of vertex in the isosceles triangle = 180-2*bottom coner= 180-65/2=50

3 angles in the equilateral triangle are equal to 60

we have 50 + 60 +h =the angle of PQR =180

h=70

Answer: h = 70°

In the triangle with Angle R = 65

It is a isoceles triangle as two sides are equal

So base angles will be equall too

Then the third angle will which is the q one will be

65+65+q = 180

q = 180 - 130

q = 50

In the other triangle with all sides equal will be equilateral triangle which means all angles equal = 60

So

Now ATQ

60 + 50 + h = 180

h = 180 - 110 (Angles on a straight line adds upto 180)

h = 70

Must click thanks and mark brainliest

Answer:

Its c

Step-by-step explanation:

Answer:

Step-by-step explanation:

SecA - TanA

= 1/CosA - SinA/CosA

= 1 - SinA/CosA

We know that Sin2A = 2SinACosA  and Cos2A = Cos²A - Sin²A

Thus SinA = Sin2(A/2) = 2Sin(A/2)CosA/2

       CosA = Cos2(A/2) = Cos²A/2 - Sin²A/2

Now substituting the values back,

=> 1 - 2Sin(A/2)Cos(A/2) / Cos²(A/2) - Sin²(A/2)

// we know that Sin²θ + Cos²θ = 1

=> Sin²(A/2) + Cos²A/2 -  2Sin(A/2)Cos(A/2) / Cos²(A/2) - Sin²(A/2)

//We know that numerator is of form a² + b² - 2ab which is (a - b)².

//Similarly denominator is of form a² - b² which is (a - b)(a + b)

=> [Sin(A/2) - Cos(A/2)]² / [Cos(A/2) + Sin(A/2)][Cos(A/2) - Sin(A/2)]

=> [ - {Cos(A/2) - Sin(A/2)}]² / [Cos(A/2) + Sin(A/2)][Cos(A/2) - Sin(A/2)]

=> [Cos(A/2) - Sin(A/2)]² /  [Cos(A/2) + Sin(A/2)][Cos(A/2) - Sin(A/2)]

=> [Cos(A/2) - Sin(A/2)] / [Cos(A/2) + Sin(A/2)]

= R.H.S

Hence proved.

Answer:

3x+ 7 =49

Step-by-step explanation:

49-7= 42

42 divided by 3 = 14

her daughter is 14 years old

I truly hope this helped, it makes sense to me. I wasn't sure whether or not you needed a more detailed equation, but that's one.

have a great day!

Answer:

y = -x+3

Step-by-step explanation:

Slope intercept form of a line is

y = mx+b where m is the slope and b is the y intercept

y = -1x +b

Using the point for x and y we can calculate b

-2 = -1(5)+b

-2 = -5+b

Add 5 to each side

-2+5 = b

3 = b

y = -x+3

Answer:

At 2

Step-by-step explanation:

I think it is because it slants down instead of going up. That is the reason why I say my answer is at 2.

HOPE THIS HELPED

Answer:

1 significant figure: 50,000 2 significant figures: 52,000 3 significant figures: 51,800

Step-by-step explanation:

FIrst, a significant figure is basically a non-zero digit (at least in your case). Basically, the 1 significant figure in your case would be to the nearest 10 thousand, which would be 50,000. Now, for 2 significant figures. This would be the nearest thousand, 52,000. Finally, 3 significant figures is to the nearest hundred, aka 51,800. Note: If you find a problem like this again 0 in between two digits that aren't 0 is a significant digit, aka the 0 in 51809. Hope this helped!

Answer:

Step-by-step explanation:

The central angle of a hexagon is 60 degrees. Drop a line from the center to the middle of the side marked 7.

Use the  tan of the angle so formed (which is 30 degrees)

Tan(30)= opposite / height (which is the line you just drew).

Tan(30) = 3.5 / h

Tan(30) = 0.5774

Tan(30) = 3.5 / h                multiply both sides by h

h*Tan(30) = 3.5                  Divide by tan30

h = 3.5 / Tan(30)

h = 3.5 / 0.5774

h = 6.062

Now from both ends of the given side, draw 2 lines to the center. Find the area of that triangle.

Area of 1 triangle = 1/2 * b * h

area of 1 triangle = 1/2 * 7 * 6.062

Area of 1 triangle = 21.2176

There are 6 such triangles so multiply that number by 6

Answer:  6 * 21.2176

Answer:  127.31

507 - 30 =  477

477 / 0.4 = 1192.5

1192.4 / 8 = 149.0625 miles or 150 miles

i don't know if this is right cause the answer seems so absurd

Answer:

The overall range is 20

Step-by-step explanation:

Given

The above dataset

Required

The overall range

Range is calculated as

[tex]Range = Highest - Lowest[/tex]

The highest of the dataset is 22, and it can be found in  Milkweed.

The lowest of the dataset is 2, and it can be found in  Daisy

So, the range is:

[tex]Range = 22 - 2[/tex]

[tex]Range = 20[/tex]

[tex]\\ \sf\longmapsto 2 \sqrt{75} - \sqrt{108} + 5 \sqrt{48} \\\\ \sf\longmapsto 2 \sqrt{25 \times 3} - \sqrt{36 \times 3} + 5 \sqrt{16 \times 3} \\ \\ \sf\longmapsto 2 \times 5 \sqrt{3} - 6 \sqrt{3} + 5 \times 4 \sqrt{3} \\ \\ \sf\longmapsto 10 \sqrt{3} - 6 \sqrt{3} + 20 \sqrt{3} \\ \\ \sf\longmapsto (10 - 6 + 20) \sqrt{3} \\ \\ \sf\longmapsto 24 \sqrt{3} [/tex]

Answer:

24aprtment3

Step-by-step explanation:

Answer:

9. Hypotenuse = √(19.1²+11.3²) = √492.5 = 22.2 m²

10. Area = (34×40)/2 + (17²×π/2)

= 680 + 453.96

= 1133.96 cm²

Answered by GAUTHMATH

Answer:

substitute for v, when v = -2.9

Step-by-step explanation:

[tex]-1.98=5.2v+13.1[/tex]

subtract 13.1 on both sides.

[tex]-15.08=5.2v[/tex]

divide by 5.2 to isolate v

[tex]\frac{-15.08}{5.2} = \frac{5.2v}{5.2}[/tex]

[tex]-2.9=v[/tex]

substitute for v

[tex]-1.98=5.2(-2.9)+13.1[/tex]

[tex]-1.98=-15.08+13.1[/tex]

[tex]-1.98=-1.98[/tex]

Answer:

A = 96 inches ^2

Step-by-step explanation:

The area of a trapezoid is given by

A = 1/2 ( b1+b2)h  where b1 and b2 are the bases and h is the height

A = 1/2( 14+10)*8

A = 1/2(24)*8

A = 12*8

A = 96 inches ^2

The area of trapezoid is given

A = 1/2 (b1+b2)h where b1 and b2 is base and h is height

A = 1/2 (14+10)*8

A = 1/2 (24)*8

A = 12 * 8

Answer:

Gloves = 11 pairs

Socks = 4 pairs

Step-by-step explanation:

Given that :

Time taken to knit pair of socks = 3 hours

Time taken to knit pair of gloves = 7 hours

Total time taken to knit 15 pairs of gloves and socks = 89 hours

Let :

number of socks = x and number of gloves = y

x + y = 15 - - - - (1)

3x + 7y = 89 - - - (2)

From (1):

x = 15 - y

Put x = 15 - y in (2)

3(15 - y) + 7y = 89

45 - 3y + 7y = 89

45 + 4y = 89

4y = 89 - 45

4y = 44

y = 44/4

y = 11

From :

x = 15 - y

x = 15 - 11

x = 4

Answer:

3x + 11

Step-by-step explanation:

1) Remove Parentheses:

x + 4 + 2x + 7

2) Combine Like Terms:

(2x + x) and (4 + 7)

3) Simplify:

3x + 11

Hope this helps, good luck! Have a good day. :)

Answer:

5.3 cents

Step-by-step explanation:

85/16

because all 16 ounces cost 85 cents

Answer:

5.3 cents.

Step-by-step explanation:

2x-y = 0

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

Work Shown:

x = (1/2)y

2x = y ... multiply both sides by 2

2x-y = 0 ... subtract y from both sides

This is in standard form Ax+By = C, where A,B,C are integers. In this case, A = 2, B = -1, C = 0.

Answer:

Approximately 17 stars

Answer:

24

Step-by-step explanation:

We need to find 60% of 40

60% * 40

.60 *40

24

He makes 24 shots

Step-by-step explanation:

60%/100%×40

60%/10%×4 (0 is cancelled)

6×4 (60 and 10 Cancelled)

24 Answer

Answer:

96 dollars and 50 cents

Step-by-step explanation:

Answer:

Đáp án:

60km

Step-by-step explanation:

30 phút

=

1

2

giờ

Ô tô đi từ A đến B rồi từ B về A mất số thời gian là:

10

−

6

−

1

2

=

3

,

5

giờ (không tính thời gian nhận hàng)

Gọi độ dài quãng đường AB là

x

(km)

Ta có:

Thời gian đi từ A đến B là

x

40

(quãng đường chia vận tốc)

Thời gian đi từ B đến A là

x

30

Ta có phương trình:

x

40

+

x

30

=

3

,

5

⇔

x

=

60

(km)

Vậy quãng đường AB là 60km.

Answer: x= 6 +/- root of 7

Step-by-step explanation:

1. Expand the left hand side: e.g, 3^2 = 3×3 =9

(x-6)(x-6) = 7

2. Multiply the brackets first by "separating" one of them, and take 7 to the left hand side:

x(x-6) - 6(x-6) =7

x^2 - 6x -6x +36-7=0

Simplify by adding like terms

x^2 -12x +29=0

3.Now your equation is in the form ax^2+bx + c =0, it means you can use the quadratic formula which is x= [-b +/- root of (b^2 - 4ac)]÷ 2a

Then SUBSTITUTE where:

a=1

b= -12

c=29

Therefore, x should be 6+ root of 7 OR 6- root of 7

Answer:

uhhhh okay thank you for removing my answer

Step-by-step explanation:

Answer:   -80

Step-by-step explanation: