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Monica [59]
3 years ago
5

What formula can you use to find the nth triangular number

Mathematics
1 answer:
Ray Of Light [21]3 years ago
6 0

Answer:

xn = n·(n + 1)/2

Step-by-step explanation:

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Sienna was dividing 12.76 by 0.001.
Solnce55 [7]
Sienna was dividing 12.76 by 0.001.Let's find out which one is correct based on the given choices. Let's perform division
=> 12.76 / 0.001 =  12 760

Thus, the correct answer is B. It will be less than 13,000. 

8 0
2 years ago
Write an equation for the table 2 5 5.6 14 7 17.5 8 20
vova2212 [387]

The equation for the table is y = 2.5 x

Step-by-step explanation:

The table is:

  • x  →  2    :    5.6    :    7    :    8
  • y  →  5    :    14      :  17.5  :    20

Lets check if the table represents the linear relation by find the ratio between the change of each two consecutive y-coordinates and the change of their corresponding x-coordinates

∵ \frac{14-5}{5.6-2}=\frac{9}{3.6}=2.5

∵ \frac{17.5-14}{7-5.6}=\frac{3.5}{1.4}=2.5

∵ \frac{20-17.5}{8-7}=\frac{2.5}{1}=2.5

∴ The rate of change between each two points is constant

∴ The table represent a linear equation

The form of linear equation is y = m x + b, where m is the rate of change and b is value y when x = 0

∵ m = 2.5

- Substitute it in the form of the equation

∴ y = 2.5 x + b

- To find b substitute x and y by the coordinates of any point

  in the table above

∵ x = 2 and y = 5

∴ 5 = 2.5(2) + b

∴ 5 = 5 + b

- Subtract 5 from both sides

∴ 0 = b

∴ y = 2.5 x

The equation for the table is y = 2.5 x

Learn more:

You can learn more about the linear equations in brainly.com/question/4326955

#LearnwithBrainly

5 0
3 years ago
Which equations have the same value of x as Three-fifths (30 x minus 15) = 72? Select three options.
Anon25 [30]

An equation is formed of two equal expressions. The correct options are C, D, and E.

<h3>What is an equation?</h3>

An equation is formed when two equal expressions are equated together with the help of an equal sign '='.

The value of x in the given equation is,

\dfrac35 (30x-15) = 72\\\\(6x - 3) = 72\\\\6x -3 = \dfrac{72}3\\\\6x = 24 + 3\\\\x = 4.5

Substitute the value of x in other option to check if the equations are equal are not. Therefore, the options can be written  as,

A.) 18x - 15 = 72

18(4.5) - 15 = 66

Thus, this will not return the same value.

B.) 50x - 25 = 72

50(4.5) - 25 = 200

Thus, this will not return the same value.

C.) 18x - 9 = 72

18(4.5) - 9 = 72

Thus, this will return the same value.

D.) 3(6x - 3) = 72

3[6(4.5) - 3] = 72

Thus, this will return the same value.

E.) x = 4.5

Thus, this will return the same value.

Hence, the correct options are C, D, and E.

Learn more about Equation:

brainly.com/question/226398

#SPJ1

7 0
2 years ago
Find the missing lengths of the sides
dusya [7]

Answer:

a=9, c=19

Step-by-step explanation:

Aight so basically in 30, 60, 90 triangles there is a formula for the sides

the hypotenuse(the longest side)=2a

The tiny side (the smallest side)=a

and the middle child =a\sqrt{3}

Based on that we see that a is 9

and since c=2a then it's 18

4 0
3 years ago
Read 2 more answers
the library is located 1.8 miles west of callies house.the grocery store is located 2.4 miles south of the library what is the l
torisob [31]

Use Pythagaras theorem :-

x^2 = 1.8^2 + 2.4^2 where a is distance required

x^2 = 9

x = 3 miles Answer

8 0
3 years ago
Read 2 more answers
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