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
N76 [4]
2 years ago
11

I think of a number, multiply it by 2 and add 1. My answer is 15. What number was I thinking of?

Mathematics
1 answer:
Yanka [14]2 years ago
5 0

Answer :: 7

<em>Explanation </em>::

Okay, I'm going to stretch this explanation long so people can understand! Hopefully this helps :) I will also provide a shorter explanation so if people want to find out how to do it quicker without details to help you understand better, they can read the shorter explanation!

- long explanation -

Equation provided from the info :: (x * 2) + 1 = 15

We need to find out what number is the x. First of all, one way to do it is do the equation backwards. And the operators will be the opposite too, for example addition is the opposite of subtraction and multiplication is the opposite of division. Now once we flip the equation it should look like this:

(15 - 1) / 2 = x

Let's break the equation apart so it's easier to work with. Remember, the rule PEMDAS. Parentheses, Exponents, Multiplication and Division, Addition and Subtraction. Why I put "and" between some words, is because they are the same level and you should go left to right from the equation. So the equation in parentheses is (15 - 1). So we just have to solve it! The answer is 14, which is an even number, so we don't have to fiddle with decimals. But if you want to know how to divide an odd natural number, feel free to comment on this answer! The equation should look like this:

14 / 2 = x

Now, all we have to do now is divide 14 in half! As someone who memorised their whole multiplication and division table, it's easy for me to figure it out. But if you haven't, try using addition! All you have to do is count up your numbers.

1 + 1 = 2

2 + 2 = 4

3 + 3 = 6

4 + 4 = 8

5 + 5 = 10

6 + 6 = 12

7 + 7 = 14!

So now we know 14 / 2 is 7. Sorry if this is too easy, I'm just giving attention to some who learn slowly, which is absolutely alright! So now we have our 2 answers. The equation now looks like this:

14 / 2 = 7.

Well we now know what the x is, and if you want to make sure it's the correct answer just flip the equation!

(7 * 2) - 1

7 * 2 = 14

14 - 1 = 15

Your answer is the same one provided, so the number is 7!

- short explanation -

The equation with the numbers provided is (x * 2) + 1 = 15

Let's flip the equation so it's easier! It should look like this:

(15 - 1) / 2 = x

Now all we have to do is solve it!

15 - 1 = 14

14 / 2 = 7

So our answer is 7! To check if the answer is correct, just re-do the unflipped equation!

(7 x 2) + 1 = ??

7 x 2 = 14

14 + 1 = 15

15 is the answer given in the text, so 7 is the correct answer.

You might be interested in
Solve for n.<br> n+ 1 = 4(n-8)<br> 0 n = 1<br> O n = 8<br> 0 n = 11<br> n = 16<br> ?
Irina18 [472]
N=11
I’m not 100% sure
Hoped this helped
6 0
3 years ago
Read 2 more answers
Mane who be shaking dice?
skelet666 [1.2K]

Not me

Step-by-step explanation:

5 0
3 years ago
Read 2 more answers
Consider the equation LaTeX: pN=kVT p N = k V T , where k is a constant. Select all of the correct answers that describe the var
a_sh-v [17]

Answer: did u ever get the right answer?

Step-by-step explanation:

8 0
3 years ago
Fill in the blank with a constant, so that the resulting expression can be factored as the product of two linear expressions: 2a
sdas [7]

Answer:

-15

Step-by-step explanation:

We proceed as follows;

In this question, we want to fill in the blank so that we can have the resulting expression expressed as the product of two different linear expressions.

Now, what to do here is that, when we factor the first two expressions, we need the same kind of expression to be present in the second bracket.

Thus, we have;

2a(b-3) + 5b + _

Now, putting -15 will give us the same expression in the first bracket and this gives us the following;

2a(b-3) + 5b-15

2a(b-3) + 5(b-3)

So we can have ; (2a+5)(b-3)

Hence the constant used is -15

8 0
3 years ago
Find the product. Write your answer as a mixed number in simplest form 5 3\4 x 4 2\9
qaws [65]
The product of 5 3/4 X 4 2/9 is equal to 24 5/18
4 0
3 years ago
Other questions:
  • Out of every 240 containers of juice brought in a grocery store, 116 are orange juice. what fraction purchased is orange juice
    13·2 answers
  • What is the equation of the line that is perpendicular to the given line and passes through the point (3, 0)? 3x + 5y = −9 3x +
    10·1 answer
  • (100)• (-0.09) 7th Grade math
    10·1 answer
  • I HAD TO PUT IN MATH BUT ITS PE
    7·1 answer
  • what are 3 online websites I can take pictures on with, without saving to ur device , it stays on that site and its just for u
    11·1 answer
  • Emilia and Darnell are arguing over who makes the best fruit punch. Emilia likes to use 2 cups of grape juice for every 5 cups o
    5·1 answer
  • A pizza contains 780 calories and serves two people. How many calories are in a serving?
    8·2 answers
  • Module 4 Quiz 1
    14·1 answer
  • A square has sides of length 8.4 . Work out the length of a diagnol of the square . Give your answer correct to 3 significant fi
    5·1 answer
  • The average time it takes a certain brand of ibuprofen to start working is 25 minutes, with a standard deviation of 13 minutes,
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!