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alexandr1967 [171]

3 years ago

12

An Arithmetic series has 20 terms. The first term is -81. The sum of all the terms is -480. Use the arithmetic sum formula to fi

nd the last term

1 answer:

timama [110]3 years ago

4 0

Answer:

The last term is 33.

Step-by-step explanation:

Sn = (n/2)(a1 + L) where a1 = first term and L = the last.

So:

-480 = (20/2) ( -81 + L)

-480 = 10( L - 81)

L- 81 = -480 / 10 = -48

L = -48 + 81

L = 33.

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The sum of three consecutive integers is 141. What is the smallest integer?

Sonja [21]

Answer:

The Consecutive number are 46 , 47 and 48 having sum as 141

The smallest number is 46

Step-by-step explanation:

• A consecutive numbers means number are in a sequence and are one after the another !

e.g. n , (n+1). Or 1 , 2 are consecutive numbers

• A consecutive even numbers differ by 2 because all even numbers are divisible by 2 !

• If the number is divisible by x we must had taken number as n , ( n + x ) ,

( n + 2x )

• Let the numbers be ( n - 1 ) , n and

( n + 1 )

Given ,the sum of numbers is 141

n - 1 + n + n + 1 = 141

3n = 141

n = 141/3

n = 47

So, the numbers are

n- 1 = 47 - 1 = 46

n = 47

n + 1 = 48

And , the smallest number is 46

• Verification :-

46 + 48 + 47 = 141

Which satisfies the given condition !!

Hence , verified !!

8 0

3 years ago

What is the value of p

Serjik [45]

Answer:

p = 2

Step-by-step explanation:

p + 4/p - 4

multiplying through by p,

p×p + 4/p ×p - 4×p

p² + 4 - 4p = 0

p² - 4p + 4 = 0

factorizing,

p(p - 2) -2(p - 2) =0

(p -2)(p -2) =0

p-2 =0

p=2

8 0

3 years ago

Maci and I are making a small kite. Two sides are 10". Two sides are 5". The shorter diagonal is 6". Round all your answers to t

Art [367]

Answer:

A. 4".

B. Approximately 9.54".

C. Approximately 13.54".

Step-by-step explanation:

Please find the attachment.

Let x be the distance from the peak of the kite to the intersection of the diagonals and y be the distance from the peak of the kite to the intersection of the diagonals.

We have been given that two sides of a kite are 10 inches and two sides are 5 inches. The shorter diagonal is 6 inches.

A. Since we know that the diagonals of a kite are perpendicular and one diagonal (the main diagonal) is the perpendicular bisector of the shorter diagonal.

We can see from our attachment that point O is the intersection of both diagonals. In triangle AOD the side length AD will be hypotenuse and side length DO will be one leg.

We can find the value of x using Pythagorean theorem as:

$(AO)^2=(AD)^2-(DO)^2$

$x^{2}=5^2-3^2$

$x^{2}=25-9$

$x^{2}=16$

Upon taking square root of both sides of our equation we will get,

$x=\sqrt{16}$

$x=\pm 4$

Since distance can not be negative, therefore, the distance from the peak of the kite to the intersection of the diagonals is 4 inches.

B. We can see from our attachment that point O is the intersection of both diagonals. In triangle DOC the side length DC will be hypotenuse and side length DO will be one leg.

We can find the value of y using Pythagorean theorem as:

$(OC)^2=(DC)^2-(DO)^2$

Upon substituting our given values we will get,

$y^2=10^2-3^2$

$y^2=100-9$

$y^2=91$

Upon taking square root of both sides of our equation we will get,

$y=\sqrt{91}$

$y\pm 9.539392$

$y\pm\approx 9.54$

Since distance can not be negative, therefore, the distance from intersection of the diagonals to the top of the tail is approximately 9.54 inches.

C. We can see from our diagram that the length of longer diagram will be the sum of x and y.

$\text{The length of the longer diagonal}=x+y$

$\text{The length of the longer diagonal}=4+9.54$

$\text{The length of the longer diagonal}=13.54$

Therefore, the length of longer diagonal is approximately 13.54 inches.

3 0

3 years ago

J2 + 7j + 12 = 0<br><br>CAN U PLEASE HELP ME!!!

natima [27]

Answer:

j = -3, -4

Step-by-step explanation:

j^2 + 7j + 12 = 0

(j + 3)(j + 4) = 0

j = -3, -4

3 0

3 years ago

Read 2 more answers

This is the amount you use when figuring a tip at a restaurant:

Georgia [21]

Subtotal is the total amount of all the prices you ordered, and total is the sum of the subtotal and the tip.
So it’s neither of them...

5 0

3 years ago