Question

find the value of x.
(there is a triangle with an exterior angle of 145° and an interior angle of 30°, and we need to find the angle x°.)
enter the correct number in the box.
show hints
x = \square

Explanation:

Step1: Find the adjacent interior angle

The adjacent interior angle to \(145^{\circ}\) is \(180 - 145=35^{\circ}\) (since they are supplementary angles, \(a + b=180^{\circ}\)).

Step2: Use the triangle - angle sum property

In a triangle, the sum of interior angles is \(180^{\circ}\). Let the three angles of the triangle be \(35^{\circ}\), \(30^{\circ}\), and \(x^{\circ}\). Then \(x+35 + 30=180\).
Simplify the left - hand side: \(x+65 = 180\).
Subtract 65 from both sides: \(x=180 - 65\).

Answer:

\(x = 115\)