If the 9th term of an A.P is 0, prove that its 29th term is twice its 19th term

Answers

Answer 1
Answer:

Let the first term, common difference and number of terms of an AP are a, d and n respectively.

Given that, 9th term of an AP, T9 = 0 [∵ nth term of an AP, Tn = a + (n-1)d]

⇒ a + (9-1)d = 0

⇒ a + 8d = 0 ⇒ a = -8d ...(i)

Now, its 19th term , T19 = a + (19-1)d

= - 8d + 18d [from Eq.(i)]

= 10d ...(ii)

and its 29th term, T29 = a+(29-1)d

= -8d + 28d [from Eq.(i)]

= 20d = 2 × T19

Hence, its 29th term is twice its 19th term

Answer 2
Answer:

Answer:

Proved below.

Step-by-step explanation:

a9 = a1 + 8d = 0          where a1 = first term and d = common difference.

we need to prove that

a1 + 28d = 2(a1 + 18d

simplifying:-

a1  + 36d - 28d = 0

a1 + 8d = 0 which is what we are given.

Therefore  the proposition is true.


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D -e/3d + e= e, for d​

Answers

Answer:

\large\boxed{d=(e^2+e)/(1-3e)}

Step-by-step explanation:

(d-e)/(3d+e)=e\n\n(d-e)/(3d+e)=(e)/(1)\qquad\text{cross multiply}\n\n(1)(d-e)=(e)(3d+e)\qquad\text{use the distributive property}\n\nd-e=3de+e^2\qquad\text{add}\ e\ \text{to both sides}\n\nd=3de+e+e^2\qquad\text{subtract}\ 3de\ \text{from both sides}\n\nd-3de=e^2+e\qquad\text{distribute}\n\nd(1-3e)=e^2+e\qquad\text{divide both sides by}\ (1-3e)\n\nd=(e^2+e)/(1-3e)

A full-year membership to a gym costs $325 upfront with no monthly charge. A monthly membership costs $100 upfront and $30 per month. For what numbers of months is it less expensive to have a monthly membership?

Answers

For seven months it is less expensive to have a monthly membership.

What is the arithmetic expression?

When evaluating arithmetic expressions, the stack organization is extremely efficient. We employ a number of techniques, including PEMDAS, to simplify the issue. In addition to the value, the variables also need to be made easier.

Given, A full-year membership to a gym costs $325 upfront with no monthly charge. A monthly membership costs $100 upfront and $30 per month. For calculating the number of months is it less expensive to have a monthly membership we need to create an expression where the number of months will be variable. Hence,

100 + 30x  < 325

subtract 100 on both sides

30x < 225

divide 30 into both sides

x <  225/30

x <  7.21

Therefore,  it is less expensive to have a monthly membership if we take it for seven months.

Learn more about arithmetic expressions here:

brainly.com/question/17722547

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Full year membership=$325Monthly membership= (30)(12)=360+ 100 upfront fee.Full year membership =$325Mounted membership =$460Full year membership is $100 cheaper.

Ana buys a sweater for $25.60, and it is on sale for 35% off. What is the amount of the discount?

Answers

35 percent times 25.60 equals to 8.96
25.60 minus 8.96 is 16.64

the amount of the discount is 16.64
Hey, Anayaaa!
35*25.60=8.96
25.60-8.96=16.64

Discount=$16.64
I hope this helps;)

Write the place and value of the digit 3 in each number3,476
384,400
5,437,200,184,400

Answers

1. thousands place value 3000
2. 3 hundred thousand value 300,000

PLEASE HELP!!!This is one question but with 3 parts; I answered 2 but I need one more.
Part one: Arif and Keisha go to a restaurant. their meal cost 13.75. The sales tax is 5%
I got $0.69.
Part two: They want to leave a 15% tip based on the bill and tax combined. I got $2.17
Now the part 3 I need help with says Arif ordered a more expensive meal than Keisha after tax and tip are figured he decides he should pay $3.00 more than Keisha. How much should he pay?

Answers

After you (correctly) answered part-2, you knew the total bill . . .

             (13.75 + 5%) + 15% on top of that.

             (13.75) + (0.69)  + (2.17)  =  $16.60 .

If they split the bill equally, each would pay  (1/2) (16.60) =  $8.30 .

But Arif wants to pay $3 more than Keisha.

Just take $1.50 away from Keisha's half (leave $6.80),
and add it on to Arif's half (make it $9.80).  Then their
total is the same, but his share is $3 more than her share.

                        $9.80  +  $6.80  =  $16.60

                        $ 9.80  -  $6.80  =  $ 3.00  .

What is the easiest way to find the perimeter of a triangle

Answers


The easiest way is to write down the length of each side, and then add up
the three numbers.

In fact, that's the ONLY way to find the perimeter.  If anything else needs to
be done, that's usually because you don't know all three lengths yet, and
you have to find a missing length.  Once you accomplish that, you ALWAYS
find the perimeter by adding them up.


add all the sides
side 1+ side 2+side 3= perimeter of the triangle