Question

Given that angle 3 equals 3x and angle 6 equals 6x, determine the value for x

Answer 1

When two lines are crossed by another line (like in this case), the angles matching corners are called corresponding angles:

Now, since angle 3 and angle 6 are consecutive interior angles, we have the following:

$\begin{gathered} 3x+6x=180 \\ \Rightarrow9x=180 \\ \Rightarrow x=\frac{180}{9}=20 \\ x=20 \end{gathered}$

Therefore, x=20