Question

Let x = 1 and y= -2, which expression has a negative value?

1.x+y
2.x-y
3. x times y
4. x divided by y

Answer 1

The following expressions become negative:

• 1) x+y = 1+(-2) = -1

• 3) x times y = xy = (1)(-2) = -2

• 4) x divided by y = x/y = 1/-2 = -2

Explanation:

Given

• x = 1

• y = -2

Computing by substituting x = 1, and y = -2

1) x+y = 1+(-2) = -1

2) x - y = 1 - (-2) = 1+2 = 3

3) x times y = xy = (1)(-2) = -2

4) x divided by y = x/y = 1/-2 = -2

It is clear from the above calculations that when we put x = 1, and y=-2 then the expressions (x+y), (x times y), and (x divided by y) become negative.

Therefore, the following expressions become negative:

• 1) x+y = 1+(-2) = -1

• 3) x times y = xy = (1)(-2) = -2

• 4) x divided by y = x/y = 1/-2 = -2