In a geometric figure two intersecting lines create four angles, where ∠1

and ∠3
are a vertical pair. If m∠1=(3x−25)°
and m∠3=104°
, what is the value of x
?

1 answer

To solve for \( x \) in the given problem, we can use the property of vertical angles, which states that vertical angles are equal. Since \( \angle 1 \) and \( \angle 3 \) are vertical angles, we have:

\[ m\angle 1 = m\angle 3 \]

Substituting in the values given in the problem:

\[ 3x - 25 = 104 \]

Now, we will solve for \( x \).

  1. Add \( 25 \) to both sides:

\[ 3x - 25 + 25 = 104 + 25 \]

This simplifies to:

\[ 3x = 129 \]

  1. Next, divide both sides by \( 3 \):

\[ x = \frac{129}{3} \]

Calculating the right-hand side gives:

\[ x = 43 \]

Thus, the value of \( x \) is \( \boxed{43} \).