On an equilateral triangle, each angle has a measure of 60º. Then:
[tex]2x-9=60[/tex]
Solve for x. To do so, add 9 to both sides of the equation:
[tex]\begin{gathered} \Rightarrow2x-9+9=60+9 \\ \Rightarrow2x=69 \end{gathered}[/tex]
Divide both sides of the equation by 2:
[tex]\begin{gathered} \Rightarrow\frac{2x}{2}=\frac{69}{2} \\ \Rightarrow x=34.5 \end{gathered}[/tex]
Therefore, the value of x is:
[tex]34.5[/tex]
