Question

Twice the difference of a number and 9 equals 8

Answer 1

Answer:

13 is the number.

Step-by-step explanation:

Given:

Twice the difference of a number and 9 equals 8.

Let the unknown number be 'x'.

Therefore, as per question:

The difference of 'x' and 9 = $x-9$

Twice the difference means 2 times the difference. So, we multiply 2 to the difference. Therefore,

$2(x-9)$

Now, the above expression is equal to 8. So, we equate the above expression to 8. This gives,

$2(x-9)=8$

Solving for 'x', we get:

Using distributive property of addition and distributing 2 inside the bracket. This gives,

$2\times x-2\times 9=8\\\\2x-18=8\\\\2x=8+18\\\\2x=26\\\\x=\frac{26}{2}=13$

Therefore, the unknown number is 13.

Now, we can verify our answer.

$2(13-9)=26-18=8$

Therefore, the answer is correct.