Pls answer quick if you don’t mind.

A

Step-by-step explanation:

if x=19, 19x3 =57 and 57+123=180 and straight angle = 180 so A

X=19

Step-by-step explanation:

123 and 3x are supplementary/they equal 180 added together.

Let's solve your equation step-by-step.

123+3x=180

Step 1: Simplify both sides of the equation.

3x+123=180

Step 2: Subtract 123 from both sides.

3x+123−123=180−123

3x=57

Step 3: Divide both sides by 3.

3x/3 = 57/3

x=19

Have a splendid day.

PS. I like your bakugo profile picture.

b