In this equation, there is nothing to solve for. However, the expression

is the Pythagorean theorem. If there is a right triangle, then when the lengths of two shorter legs (a and b) are added together, and then square rooted, you get c, which is the hypotenuse.
Hope this helps!
Answer:
the third angle is 50 degress
Step-by-step explanation:
the angle sum property states that the sum of all the interior angles of a triangle is 180.
therefore : 30 + 100 + x = 180
x = 180 - 130
x = 50
7 1/4 rounds to 7
5 3/4 rounds to 6
7 - 6 = 1 <== ur estimate