Q. In △PQR,PR is extended through point R to point S,m∠RPQ=(3x+15)∘, m∠QRS=(9x−13)∘, and m∠PQR=(2x−4)∘. What is the value of x?Answer:
Interior Angles of Triangle: The sum of the interior angles of a triangle is always 180 degrees. Since PR is extended through point R to point S, angle QRS is an exterior angle to triangle PQR. According to 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.
Exterior Angle Theorem Equation: Let's write the equation based on the exterior angle theorem:m/RPQ+m/PQR=m/QRS(3x+15)+(2x−4)=(9x−13)
Combine Like Terms: Now, let's combine like terms:3x+2x+15−4=9x−135x+11=9x−13
Solve for x: Next, we will solve for x by moving the x terms to one side and the constant terms to the other side: 5x−9x=−13−11−4x=−24
Final Solution: Now, divide both sides by −4 to solve for x:x=−4−24x=6
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