Let's assume
that number is x
now, we are given
The difference between nine times a number an 7 is -70
nine times of that number is 9x
so, we can set up equation
[tex] 9x-7=-70 [/tex]
now, we can solve for x
[tex] 9x-7+7=-70+7 [/tex]
[tex] 9x=-63 [/tex]
[tex] x=-7 [/tex]
so, number is -7.........Answer
