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A number is added to 12, and the result divided by 2. the answer is the same as you get by subtracting the number from 4. what is the number?​

User Shparekh
by
4.9k points

2 Answers

5 votes

Answer:

the number is 20

Explanation:

Equation: let x be the missing number

x + 12 ÷ 2 = x - 4

first step: multiply 2 on both sides to get rid of the division

x + 12 ÷ 2 × 2 = x - 4 × 2

x + 12 = 2x - 8

second step: add 8 on both sides:

x + 12 + 8 = 2x - 8 + 8

x + 20 = 2x

third step: subtract x on both sides:

x - x + 20 = 2x - x

20 = x

to check: substitute 20 for x

x + 12 ÷ 2 = x - 4

20 + 12 ÷ 2 = 20 - 4

32 ÷ 2 = 16

16 = 16

User Vincent Sit
by
5.5k points
4 votes

Answer:

1 1/3

Explanation:

(x+12)/2 = 4-x

Step 1, multiply both sides by 2 to remove that pesky fraction. x+12 = 8–2x

Step 2, add 2x to both sides to remove x from the right hand side. 3x+12 = 8

Step 3, minus 12 from both sides, removing it from the left hand side. 3x = -4

Step 4, divide by 3. x = 1 1/3

User Leonardus Chen
by
5.0k points