Question

What is the sum of 5x - 6y + z and 5x - 6y - z

Answer 1

solution,

5x-6y+z+5x-6y-z

(+z and -z will be cancelled)

now,

5x+5x-6y-6y

10x+ 12y( because 2 minus makes plus)

Answer 2

5x - 6y + x + 5x - 6y - z

Combine like terms:

5x - 6y + 1z + 5x - 6y - 1z (the ones’ are usually invisible)
10x - 12y (positive and negatives cancel out)

Final answer: 10x - 12y


Hope this helps!