Question

If A = 5, B = -7 and C = -8 Evaluate each expression. Then
A - B - C ?
-A + B - C ?
A + B + C ?
A - B + C ?

Answer 1

A-B-C
$5 - ( - 7) - ( - 8) \\ = 5 + 7 + 8 \\ = 20$
The answer is 20

-A+B-C
$- 5 + ( - 7) - ( - 8) \\ = - 5 - 7 + 8 \\ = - 4$
The answer is -4

A+B+C
$5 + ( - 7) + ( - 8) \\ = 5 - 7 - 8 \\ = - 10$
The answer is -10

A-B+C
$5 - ( - 7) + ( - 8) \\ = 5 + 7 - 8 \\ = 4$
The answer is 4

Answer 2

1)5-(-7)-(-8)
=5+7+8
20

2)-5+(-7)-(-8)
-5+(-7)+8
-12+8
= -4

3)5+(-7)+(-8)
= -10

4)5-(-7)+(-8)
12+(-8)
12-8
=4