Answer:
x = 12
Step-by-step explanation:
The two angles are complementary since they form a 90 degree angle.
35+ 4x+7 = 90
Combine like terms
42 +4x = 90
Subtract 42 from each side
42-42 +4x =90-42
4x = 48
Divide each side by 4
4x/4 = 48/4
x = 12
There are 3 sides. If you draw out a triangle, each line is a separate side (a line segment connecting 2 vertices, or points). You can also see in the word "triangle" the prefix "tri-", meaning "three". It refers to the shape having 3 angles, but when there are 3 angles there are 3 sides to make it up. This is true for other shapes too - in a square, there are 4 sides connecting 4 points, and between each side is an angle, creating 4 angles.