A line adds up to equal 180 degrees. And adjacent angles also add to equal 180 since they share a side on a line. So add them together and make them equal 180
9x - 7 + 8.5x + 4 = 180
17.5x - 3 = 180
17.5x = 183
x = 10.5
Answer:
Step-by-step explanation:
<h3>What are the definitions?</h3>
- Obtuse triangle - the triangle with angle greater than 90°;
- Acute triangle - the triangle with all interior angles under 90°;
- Isosceles triangle - the triangle with a pair of equal sides;
- Scalene triangle - the triangle with all three sides (or angles) of different measure.
<h3>What we have?</h3>
- All sides are different and all angles are under 90°.
<h3>Which option is correct?</h3>
I think this is the answer :)