Question 976948
Assume the number is x
9 is added to the number = x + 9
The sum is doubled = 2(x + 9)
The result is -8 less than the number
= x - (-8) = x + 8
Therefore 2(x + 9) = x + 8
Multiply and sort out:
2x + 18 = x + 8
2x - x = 8 - 18
 x = -10
2(x + 9) = x + 8
2(-10 + 9) = -10 + 8
 -2 = -2
Hope this helps:-)