Answer:
A) 30x
Explanation:
Given equation:
5(x – 2x + 6x + 10) = 5x – 10x + ? + 50
Let the "?" be represented as "a". Then,
⇒ 5(x – 2x + 6x + 10) = 5x – 10x + a + 50
[Right hand side] Put all the terms inside a parenthesis (except "a").
⇒ 5(x – 2x + 6x + 10) = 5x – 10x + a + 50
⇒ 5(x – 2x + 6x + 10) = (5x – 10x + 50) + a
Isolate the "a" on one side by subtracting the terms inside the parenthesis.
⇒ 5(x – 2x + 6x + 10) - (5x – 10x + 50) = (5x – 10x + 50) + a - (5x – 10x + 50)
⇒ 5(x – 2x + 6x + 10) - 5x + 10x - 50 = a
[Left hand side] Simplify the distributive property
⇒ 5(x – 2x + 6x + 10) - 5x + 10x - 50 = a
⇒ (5x – 10x + 30x + 50) - 5x + 10x - 50 = a
[Left hand side] Open the parentheses
⇒ (5x – 10x + 30x + 50) - 5x + 10x - 50 = a
⇒ 5x – 10x + 30x + 50 - 5x + 10x - 50 = a
[Left hand side] Combine like terms and simplify
⇒ 5x – 10x + 30x + 50 - 5x + 10x - 50 = a
⇒ x(5 – 10 + 30 - 5 + 10) + (50 - 50) = a
⇒ x(30) = a
[Left hand side] Open the parenthesis and simplify
⇒ x(30) = a
⇒ 30x = a = ?
Therefore, the correct option is A (30x).