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
Elan Coil [88]
3 years ago
6

How can you use a pattern to add 20+30+40+50+60+70+80​

Mathematics
1 answer:
Usimov [2.4K]3 years ago
8 0

Answer:

\displaystyle \: \: \: \: 7 \\ \: \: \sum \: (10n + 10) \\ n = 1

Step-by-step explanation:

You can use Summation Notation as a pattern to evaluating "20 + 30 + 40 + 50 + 60 + 70 + 80":

\displaystyle \: \: \: \: 7 \\ \: \: \sum \: (10n + 10) \\ n = 1

I am joyous to assist you anytime.

You might be interested in
Please help!
Darya [45]

Answer:

x = 6.5

Step-by-step explanation:

In order to solve this problem, you need to use trigonometry (sin, cosine, tangent).  

Sin = opposite/hypotenuse

Cosine = adjacent/hypotenuse

Tangent = opposite/adjacent

We need to use tangent in this case because 10 is the opposite side from the 57° angle, and x is right next to it, making it adjacent.  So, our equation would look like this:

tan (57)° = 10/x

Multiply both sides by x

x (tan (57)°) = 10

Divide both sides by tan (57)°

10 / tan (57)° = 6.49408 = 6.5

6 0
3 years ago
Read 2 more answers
Can y’all give me some awnsers and number to them?
lesantik [10]

Answer:

1.  16 cm (squared)

3. 200 cm (squared)  

Step-by-step explanation:

5 0
3 years ago
A student claims that the equation y=7 id not a linear equation because it does not have the form y=mx+b.
Misha Larkins [42]


I disagree, the equation is in y=mx+b form.  The slope, or m, is 0, so the equation is y=0x+7.  That simplifies to y=7.

5 0
4 years ago
In the function f(x) = 6x + b, what must be the value of b, if f(5) = 1?
Brut [27]
<h3>Answer:    -29</h3>

=============================================

Work Shown:

f(x) = 6x + b

f(5) = 6(5) + b .... replace every x with 5

f(5) = 30 + b

1 = 30 + b ..... replace f(5) with 1, since f(5) = 1 was given.

1-30 = 30 + b - 30 .... subtract 30 from both sides

-29 = b

b = -29

-----------

The function f(x) = 6x+b turns into f(x) = 6x+(-29) which is equivalent to f(x) = 6x-29

Plugging in x = 5 leads to

f(x) = 6x-29

f(5) = 6(5) - 29

f(5) = 30 - 29

f(5) = 1

So we have confirmed the answer.

5 0
3 years ago
Read 2 more answers
Solve the equation step by step
LekaFEV [45]

Let <em>x</em> be the amount of salt in the solution.

At day's end, the concentration of salt in the beaker is

<em>x</em> / (4 L) = 0.08 = 8%

Solve for <em>x</em> to get

<em>x</em> = 0.08 (4 L) = 0.32 L

So at the beginning, the concentration of salt in the beaker was

(0.32 L) / (5 L) = 0.064 = 6.4%

7 0
3 years ago
Other questions:
  • The book Doug is reading is 280 pages long.He has read 84 pages so far.What percent of his has Doug read
    5·2 answers
  • Please Help!!! I will Give Brainliest!!!!!
    14·1 answer
  • The base price of a new car is $24,789. The option for the sports package is $2529. Estimate the price of the car with the
    13·1 answer
  • A discount voucher offering 15% off is used to pay a bill. After using the voucher, the bill is reduced to £36.72.
    5·2 answers
  • What is the value of x
    13·1 answer
  • What is -1(4/5)<br> I'm stuck on this question
    15·2 answers
  • Help! Absolute value equations
    10·2 answers
  • Guys anyone please help . Please explain how to solve these questions it gives the answers but I need expiation (Calculus) ,I’ll
    10·1 answer
  • Please someone help!! I tried my best to complete this problem but i'm stuck now (also am i even doing it right so far??!);(
    11·1 answer
  • Brett and Lionel start out together to bike from Windsor Forrest to Camperdown, a distance of 36 miles.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!