The difference of twice a number and 7 is 9

Question

I need to know this in an equation form

Answer 1

"Difference" indicates subtraction.

1)Let "x" be the value of the unknown number.

2) Let "2x" be twice the unknown number.

3) Let 2x - 7=9; 9 is the difference between the unknown number and 7.

4) Solve for x.

2x - 7=9

+7=+7

2x=16

x=16/2

x=8

Answer 2

Assuming the number is x,

2 x - 7 = 9

thus

2x = 16

so

x=8