Question

which equation can be used to solve for x?
2x + 3x = 71
7x - 6 = 71
11x - 6 = 71
2x + 3 = 71
solve for x.
x =

Explanation:

Step1: Use the exterior angle theorem

The measure of an exterior angle of a triangle is equal to the sum of the measures of the two non - adjacent interior angles. Here, \(2x+(9x - 6)=71\). Simplify the left - hand side: \(2x+9x-6 = 71\), which gives \(11x-6 = 71\).

Step2: Solve the equation \(11x-6 = 71\) for \(x\)

Add \(6\) to both sides of the equation: \(11x-6 + 6=71 + 6\), so \(11x=77\).
Divide both sides by \(11\): \(x=\frac{77}{11}\).

Answer:

\(x = 7\)