Answers

2016-07-13T19:32:28+08:00
Let us represent the two numbers as x and y.

x / y  = -9   ... [1]
x + y = -64 ... [2]

Manipulate [2]
x + y = - 64
x = - y - 64

Substitute in [1]
x / y = - 9
(-y - 64)/y = -9
-1 - 64/y = -9
1 + 64/y = 9
y + 64 = 9y
64 = 8y 
8 = y

x = -y - 64
   = - 8 - 64
   = - 72

Thus x = -72 and y = 8
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