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
aleksandr82 [10.1K]
3 years ago
5

If the 7th of an AP is equal to 11 times the 11th term, find the 18th term

Mathematics
1 answer:
Zina [86]3 years ago
3 0

Answer:

-33 or 33

Step-by-step explanation:

The seventh term of an AP is written as:

a + 6d

The eleventh term of an AP is written as:

a + 10d

If the 7th term is 11 times the 11th term, then;

a + 6d = 11(a + 10d)

Expand to get:

a + 6d = 11a + 110d

11a - a = 6d - 110d

10a =  - 104d

\frac{a}{d}  = -   \frac{104}{10}

\frac{a}{d}  = -   \frac{52}{5}

We must have a=-52 and d=5

Or

a=52 and d=-5

For the first case, the 18th term is :

- 52 + 5 \times 17 = 33

For the second case,

52 - 5 \times17 =  - 33

You might be interested in
Two similar pyramids have base areas of 12.2 cm2 and 16 cm2. The surface area of the larger pyramid is 56 cm2. What is the surfa
docker41 [41]

Given =

Two similar pyramid have base area of 12.2 cm² and 16 cm².

surface area of the larger pyramid = 56 cm²

find out the surface area of the smaller pyramid

To proof =

Let us assume that the surface  area of the smaller pyramid be x.

as surface area of the larger pyramid is 56 cm²

Two similar pyramid have base area of 12.2 cm² and 16 cm².

by using ratio and proportion

we have

ratio of the base area of the pyramids : ratio of the surface area  of the pyramids

\frac{12.2}{16} : \frac{x}{56}

x = 12.2 ×56×\frac{1}{16}

by solvingthe above terms

we get

x =42.7cm²

Hence the surface area of the smaller pyramid be 42.7cm²

Hence proved










3 0
3 years ago
Read 2 more answers
If f(x) = x2 -1, what is the equation for f–1(x)?
professor190 [17]
Evaluate the function would be= x^2-f-x
3 0
3 years ago
At one time the aircraft is 150 m above the surface, the submarine is 25 m below the surface, and the underwater robotic vehicle
EastWind [94]

Answer:

175 meter is  difference in height between the submarine and the aircraft

Step-by-step explanation:

The height of aircraft above the surface = 150 meter

Depth at which the submarine lies below the surface = 25 meter

Depth at which the underwater robotic vehicle  below the surface = 186 meter

Difference in height between the submarine and aircraft is equal to

25 +150 = 175 meter

4 0
3 years ago
If f(x) = x2 – 2x, find:<br><br> f(6)=
creativ13 [48]

Answer:

0

Step-by-step explanation:

When x=6

f(6) =(6)2-2(6)=12-12=0

8 0
3 years ago
Read 2 more answers
What is the approximate volume of the oblique cone? Use π ≈ 3.14 and round to the nearest tenth. 117.8 cubic units 141.3 cubic u
Tom [10]

Answer:

The answer is 235.5 :)

Step-by-step explanation:

Step-by-step explanation:

3 0
3 years ago
Read 2 more answers
Other questions:
  • The length and width of a rectangle are 5 feet and 2 feet, respectively. A similar rectangle has a width of 8 feet. What is the
    11·2 answers
  • How to convert 8.5 hours to hours and minutes
    12·1 answer
  • There are 62 rows of 9 chairs about how many chairs are there???
    11·1 answer
  • Simplify the expression by combining like terms.<br><br> 1/2d - 3/4d + 3f - 2f
    5·2 answers
  • What is 10 1/4 - 2 2/4
    11·1 answer
  • Keiko, Tony, and Frank sent a total of 121 text messages during the weekend. Tony sent 3 times as many messages as Frank. Keiko
    5·1 answer
  • What is the slope of a line perpendicular to the line whose equation is 3x-3y=543x−3y=54. Fully simplify your answer.
    7·1 answer
  • This question has four parts. Two football games were played at a stadium on the same day. Part A At the start of the first game
    11·1 answer
  • Tyler's family has 4 children. How many ways can they line up to get their flu shot at the doctor?
    5·1 answer
  • 15 points!
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!