Question

given $m\parallel n$, find the value of x.

Explanation:

Step1: Identify supplementary angles

The two angles are same-side interior angles, so they sum to $180^\circ$.
$$(3x-23) + (7x-7) = 180$$

Step2: Combine like terms

Simplify the left-hand side.
$$10x - 30 = 180$$

Step3: Isolate the variable term

Add 30 to both sides of the equation.
$$10x = 210$$

Step4: Solve for x

Divide both sides by 10.
$$x = \frac{210}{10}$$

Answer:

$21$