Answer:
[tex]x = \frac{y + z - a}{3}[/tex]
Step-by-step explanation:
Step 1: Subtract a from both sides
[tex]a + 3x - a = y + z - a[/tex]
[tex]3x = y + z - a[/tex]
Step 2: Divide both sides by 3
[tex]\frac{3x}{3} = \frac{y + z - a}{3}[/tex]
[tex]x = \frac{y + z - a}{3}[/tex]
Answer: [tex]x = \frac{y + z - a}{3}[/tex]
