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
Tresset [83]
3 years ago
7

The 8th and 20th terms of an arithmetic sequence are 20 and 56 respectively. ​What is the 1st term of the sequence.

Mathematics
1 answer:
Ostrovityanka [42]3 years ago
6 0

Answer:

<h3>             a₁ = -1</h3>

Step-by-step explanation:

a_n=a_1+d(n-1)\\\\a_8=a_1+d\cdot7\\\\a_{20}=a_1+d\cdot19\\\\a_{20}-a_8=a_1+19d-(a_1+7d)=12d\\\\56-20=2d\\\\12d=36\\\\d=3\\\\\\ a_1+3\cdot7=20\\\\a_1=20-21=-1

You might be interested in
Write an expression to match the statement below Add 5 to 48 divided by 12
Sergeeva-Olga [200]

Answer:

49

Step-by-step explanation:

48+ 5 = 53 divided by = 49

8 0
3 years ago
An item is priced at $80. It is on sale for 20% off the regular price. What is the sale price?
Masja [62]
Regular Pirce = $80.

Discount = 20%

Discount = 20% x $80 = 0.2 x 80 = $16

Sale Price = 80 - 16 = $64

----------------------------------------------------
Answer: The Sale Price is $64.
----------------------------------------------------
4 0
3 years ago
-66/22 to a decimal PLEASE I NEED THE ANSWER!!! I'LL MARK BRAINLIEST ​
maria [59]

Answer: -3

Step-by-step explanation:

6 0
3 years ago
Read 2 more answers
PLEASE HELP ME. NO PHONY ANSWERS TY, ANSWER IF YOUR 100% RIGHT!
Ksivusya [100]

The relative frequency of female mathematics majors will be 0.5142.

<h3>How to find the relative frequency?</h3>

The proportion of the examined subgroup's value to the overall account is known as relative frequency.

A sample of 317 students at a university is surveyed.

The students are classified according to gender (“female” or “male”).

The table is given below.

Then the relative frequency of female mathematics majors will be

⇒ 36 / (36 + 34)

⇒ 36 / 70

⇒ 0.5142

Learn more about conditional relative frequency here:

brainly.com/question/8358304

#SPJ1

8 0
2 years ago
What is the value of x? 6x - 2x = 16
agasfer [191]

6x - 2x = 16

4x = 16    |divide both sides by 4

<h3>x = 4</h3>
5 0
3 years ago
Read 2 more answers
Other questions:
  • In triangle ABC, m∠ABC = (4x – 12)° and m∠ACB = (2x + 26)°. Yin says that if x = 19, the triangle must be equilateral. Is he cor
    13·2 answers
  • Estelle drew two parallel lines PQ and R0S intersected by a transversal KL, as shown below: Which theorem could Estelle use to s
    10·2 answers
  • Let f(x)=x^2−4x. Solve f(x)=−4.
    5·1 answer
  • Ms.McKeary is making Holiday Day cards with stickers.she bought 4 sheets of stickers,with 12 stickers per sheet . If Ms.McKeary
    9·1 answer
  • ¿Cuántas libras de café “La Finca” que se vende a $5 la libra debe mezclarse con 80 libras decafé común que se vende a $2 la lib
    14·1 answer
  • Points W X and y are collinear (that is on the same line). Write and solve an equation to find m
    7·1 answer
  • HURRY PLEASE 6TH GRADE MATH HERE. A football field is 100 yards in length. How many inches long is a football field? 300 inches
    7·2 answers
  • 13.) In 1990, a radio costs $25. Now,<br> the radio costs $5. What is the<br> percent of change?
    8·1 answer
  • Which graph represents the solution set to this system of inequalities?
    11·1 answer
  • Fill in the missing<br> number to make the<br> number sentence<br> true.<br> | 148 +___= 179
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!