Just good ole algebraic manipulation
[tex]2a - b = 8b - 4a [/tex]
First, Let's Combine Common Terms
[tex](2a + 4a) = (8b + 1b) \\ 6a = 9b[/tex]
Now Let's Divide
[tex] \frac{6a}{6} = \frac{9b}{6} \\ a = \frac{9b}{6} [/tex]
Let's Simplify That Fraction
[tex]a = \frac{9}{6} \times \frac{b}{1} \\[/tex]
Answer
[tex]a = \frac{3b}{2} \: [/tex]
