Question

1. (9x - 3)° x = ____

Explanation:

Step1: Recognize the triangle type

The triangle is equilateral since all sides are marked equal. In an equilateral triangle, each interior - angle is 60°.

Step2: Set up the equation

We set the given angle expression equal to 60°, so $9x - 3=60$.

Step3: Solve for x

Add 3 to both sides of the equation: $9x=60 + 3$, so $9x=63$. Then divide both sides by 9: $x=\frac{63}{9}$.

Answer:

$x = 7$