Question

1) What is -2y + 10 + 2y - 8 simplified? 2) Evaluate: -x(y - x) + (3x - y)when x = -2 and y = 5

Answer 1

Answer:

1) 18 2) 17

Step-by-step explanation:

1) -2y + 10 + 2y - 8

= 2y - 2y + 10 + 8 [collecting like terms]

= 0 + 10 + 8 [subtracting like terms]

= 18

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

according to question,

- (- 2){5 - (- 2)} + {3 × (- 2) - 5} [putting x as (- 2) and y as 5]

= + 2(5 + 2) + (- 6 - 5)

= 2 × 14 + (- 11)

= 28 - 11

= 17

______________

Explanations:

1) Here, we just have to collect the like terms which are containing x, y, z, etc. and also we have to collect the terms not containing x, y, z, etc. and keep them on the other side, after that we will do the simply using required rules.

2) Here at first, we will put the values of the unknown terms according to the question and then simplify them using rules like BODMAS.

*******************