Can someone help me with 9,10, and 11 please you don’t have to do all of them just atleast one for me

Hi! So what you will need to know is pythagorean theorm.
What the theorm basically says is a^2 + b^2 = c^2.
-- The (a,b,c) are referring to the sides of the triangles (3 letters for 3 sides).
Take note that "c" is always the side opposite of the right angle.
The other known side could be "a" or "b"
Taking a look at problem 9, identify the "c" value. The "c" value would be 35.
Then indentify the value of "b" or "a". "a" would = 20.
Plug it into the equation:
20^2 + b^2 = 35^2
400 + b^2 = 1225
solve for b.
1. subtract 400 from both sides.
b^2 = 825
b = [tex]\sqrt{825}[/tex]
you could solve for the square root but it would give a decimal numbers but I'm not sure what the teacher is looking for.