1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Elena-2011 [213]
3 years ago
13

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

Mathematics
2 answers:
Ghella [55]3 years ago
6 0

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

Scilla [17]3 years ago
5 0

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.

You might be interested in
The order pairs (1, 2), (2, 5), (3, 10), (4, 17), and (5, 26) represent a function. what is a rule that could represent this fun
LenaWriter [7]
The X which is the first number in each () in called the input
There is only one input for every number
Meaning all the first numbers mystery br DIFFERENT
6 0
3 years ago
Find the area of the trapazoid for me please :)
Doss [256]

Answer:

A = 14 m^2

Step-by-step explanation:

The area of a trapezoid is found by

A = 1/2 (b1+b2) *h  where b is the length of the bases and h is the height

A = 1/2 (2+5) *4

A = 1/2(7)4

A = 14 m^2

6 0
3 years ago
Simplify: −2[−3(x − 2y) + 4y]. <br> thanks!
Neporo4naja [7]

Answer:

6x − 20y

Step-by-step explanation:

−2[−3(x − 2y) + 4y] =

= −2[−3x + 6y + 4y]

= −2[−3x + 10y]

= 6x − 20y

5 0
3 years ago
Read 2 more answers
Evaluate [(21 + 6) − 32] ק 9 ⋅ 2.
anzhelika [568]
OK.......
Evaluating [(21 + 6) - 32] 2 * 9 ק
Your answer would be 
-90 

H0P3 It H3LPS :)
8 0
3 years ago
Simplify the product.
Marina86 [1]
(x - 4)(x + 3) = x^2 + 3x - 4x - 12 = x^2 - x - 12
8 0
3 years ago
Read 2 more answers
Other questions:
  • Can anyone solve the 8th question given below??? Urgent!!
    9·1 answer
  • Which shows one way to determine the factors of 4x3 + x2 - 8x - 2 by grouping?
    15·2 answers
  • How is shading a grid to show 1 tenth different from shading a gird from 100?
    13·2 answers
  • I need know the answer
    14·2 answers
  • 181.93 divided by -11.3
    11·2 answers
  • "At Truman Middle School, 2/3 of the girls surveyed preferred playing capture the flag at gym. If 600 girls responded to the sur
    15·1 answer
  • Starbucks sold 200 coffees in the last hour, 40 of which were lattes. What is the probability that the next drink sold will be a
    6·2 answers
  • -2,-5,-8,-11 41st term
    9·2 answers
  • 7) A store is selling videogames for p dolars. Write an equation that represents the total amount. T. for
    6·1 answer
  • HELP PLS ASAP I NEED HELP PLS HELP ANSWER THE QEUSTION IN THE PHOTO PLS I GIVE BRAINLEST TO CORRECT ANSWER
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!