Question

when 7 is added to an unknown number the answer is twice the unknown number .what is the unknown number ​

Answer 1

7

Step-by-step explanation:

Let's call the unknown number n.

7 + n

7 + n = 2n

Isolate the variable by subtracting n from each side.

7 = n.

The unknown number is 7.

Answer 2

The unknown number is 7.

Step-by-step explanation:

If you're adding 7 to it, and it becomes twice of itself. Meaning the unknown number, x. Was multiplied by a factor of 2. So 2x. Or 7+x=2x.