Question

in $\triangle stu$, $mangle s=(10x + 11)^{circ}$, $mangle t=(x + 6)^{circ}$, and $mangle u=(2x - 6)^{circ}$. what is the value of $x$?

Explanation:

Step1: Recall angle - sum property

The sum of angles in a triangle is 180°. So, $(10x + 11)+(x + 6)+(2x-6)=180$.

Step2: Combine like - terms

$10x+x + 2x+11 + 6-6=180$, which simplifies to $13x+11 = 180$.

Step3: Isolate x

Subtract 11 from both sides: $13x=180 - 11=169$. Then divide by 13: $x=\frac{169}{13}=13$.

Answer:

13