Can someone with these 3 i am so confused on what to do

26.

27.

28.

Step-by-step explanation:

26. :

Taking square on both the sides to get:

For non-negative values for radical:

So solution for this:

27.

Subtracting 2 from both the sides to get:

Taking square root on both sides:

28.

Adding to both the sides to get:

Taking square on both sides:

Subtracting from both sides to get:

Subtracting 4 from both sides:

Square both sides again:

and for non-negative radical

therefore, solution is .