to #1: Expand the brackets, collect all terms with the variable at the LHS of the equation:

-1/6(x-18)+1/3(x+3)=x+4 <==> -1/6x+3 + 1/3x + 1 = 4 <==>1/6x=0 <==> x = 0

to #2:

There are 2 different ways to do the question:

First transform the mixed numbers into fractions and then subtract

or

subtract integers and fractions separately:

to #3:

You are dealing with a right triangle. Use the Pythagorean theorem. The lengths of the sides are known to you:

a = l -16

b = l - 2

c = l

Therefore:

Solve for l:

I've got x = 10 or x = 26

You have to decide which solution could be right

**and why!**