Question

1st semester exam
find the missing angle, and classify the triangle as acute, obtuse or right.
(image of a triangle with angles 45° and 88°, and a missing angle ?)
desmos
○ 57° right
○ 53° acute
○ 47° acute
○ 133° obtuse

Explanation:

Step1: Recall triangle angle sum

The sum of angles in a triangle is $180^\circ$. Let the missing angle be $x$. So, $x + 45^\circ + 88^\circ = 180^\circ$.

Step2: Solve for x

Simplify the equation: $x + 133^\circ = 180^\circ$. Subtract $133^\circ$ from both sides: $x = 180^\circ - 133^\circ = 47^\circ$.

Step3: Classify the triangle

All angles ($45^\circ$, $88^\circ$, $47^\circ$) are less than $90^\circ$, so the triangle is acute.

Answer:

$47^\circ$ acute (corresponding to the option: $47^0$ acute)