Question

find an expression which represents the sum of (-4x - 10y) and (9x - 10y) in simplest terms.

Explanation:

Step1: Write the sum expression

$(-4x - 10y)+(9x - 10y)$

Step2: Remove parentheses

$-4x - 10y+9x - 10y$

Step3: Combine like - terms

$(-4x + 9x)+(-10y-10y)$
$=5x-20y$

Answer:

$5x - 20y$