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2 votes
Seven more than one number equals nine less than double that number. Find that number.

User JTG
by
6.1k points

2 Answers

1 vote
Answer:
That number is 16

Step-by-step explanation:
Step 1 - Write down the information you know

*ps. for this problem we will be using x to represent the unknown number. for future problems, just know that unless a variable has an assigned letter to represent it, you can usually pick whichever letter you’d like

• “Seven more” — “7 +”
• “then one number equals” — “x =”
• “nine less than” — “- 9”
• “double that number” — “2x”

Step 2 - Write an equation using the information you know

x + 7 = 2x - 9

Step 3 - Subtract x from both sides of the equation

x + 7 = 2x - 9
x - x + 7 = 2x - x - 9
7 = x - 9

Step 4 - Add 9 to both sides of he equation and then switch sides

7 = x - 9
7 + 9 = x - 9 + 9
16 = x
x = 16

Now that we have found the value of x, we know that the number is 16.
User Kerianne
by
6.3k points
7 votes

Answer: That number is 16.

Step-by-step explanation:

n + 7 = 2n- 9 n represents the number now solve the question

+ 9 +9 add 9 to both sides

n + 16 = 2n subtract n from both sides

-n -n

16= 1n Divide both sides by 1

n= 16

Check: 16 + 7 = 2(16) - 9

23 =23

User Malcolm Box
by
5.9k points