Answer:
degrees
Step-by-step explanation:
Angles on a straight line add up to 180 degrees.
Thus, 

Divide both sides by 4:


20 and 7 Because 4x5 = 20
Answer:
10x+23 (pretty sure) and the * means multiply
Step-by-step explanation:

Answer:
B. the triangle in question is not a right triangle
Step-by-step explanation:
A 3-4-5 triangle is a right triangle, so this one, with its longer longest side, is an obtuse triangle. It is not a right triangle.
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3, 4, 5 is one of the first Pythagorean triples that you learn:
3² + 4² = 5²
These are the side lengths of the smallest right triangle with integer sides. It is worthwhile to remember. This triple is used not only in many math problems (such as this one), but also in real life when it is useful to lay out a right angle.
4 +5 = 9 and 12 + 3 =15 and there is more than this
hope I helped