Hey there!
x + 2x - 5 + 6 = 0
1x + 2x - 5 + 6 = 0
3x + 1 = 0
SUBTRACT 1 to BOTH SIDES
3x + 1 - 1 = 0 - 1
CANCEL out: 1 - 1 because that gives you 0
KEEP: 0 - 1 because that helps solve for the x-value
0 - 1 = -1
NEW EQUATION: 3x = -1
DIVIDE 3 to BOTH SIDES
3x/3 = -1/3
CANCEL out: 3/3 because that gives you 1
KEEP: -1/3 because it gives you the value of x
SIMPLIFY IT
x = -1/3
Therefore, your answer is: x = - 1/3
Good luck on your assignment and enjoy your day!
~Amphitrite1040:)