Find two numbers a and b whose sum a + b is -2 and whose difference a − b is 6. Your answer is a = ? b =?

Question

Value/Interest Problems

Answer 1

   a + b = -2

+(a - b = 6)

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  2a      = 4

   a = 2

 

a - b = 6

2 - b = 6

2 - 6 = b

-4 = b

Answer 2

a+b = -2

 

a-b = 6

 

 

Adding the equations together:

  2a = 4

 So a = 2

 

 2 + B = -2

 2+b - 2 = -2 -2

 b = -4

 

A=2 B = -4