Question

Раскройте скобки: б) -x – (-3p – 2y) в) – (m – 2n) + (3a + b) г) (x – 5) – (7 – x) + (9 – x)

Answer 1

Б) -x + 3p + 2y
в) -m +2n + 3a + b
г) x - 5 - 7 + x + 9 - x

Answer 2

a) -x - (-3p - 2y)

To remove the parentheses, we apply the distributive property of multiplication over addition/subtraction, which states that a(b + c) = ab + ac.

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

b) -(m - 2n) + (3a + b)

To remove the parentheses, we apply the distributive property again.

-(m - 2n) + (3a + b) = -m + 2n + 3a + b

г) (x - 5) - (7 - x) + (9 - x)

Let's simplify this expression step by step:

1. Remove the inner parentheses: (x - 5) - (7 - x) + (9 - x) = (x - 5) - 7 + x + 9 - x

2. Combine like terms: x - 5 - 7 + x + 9 - x = (x + x - x) - 5 - 7 + 9

Since we have x + x - x, the x terms cancel each other out.

3. Simplify further: (x + x - x) - 5 - 7 + 9 = 0 - 5 - 7 + 9 = -5 - 7 + 9 = -12 + 9 = -3

The result is -3.