u-2√2=3. please show work

What part of my work don't you understand?

u - √2 = 3

u - 1.414 = 3

u = 4.414

the answer should be 9

sorry. u-2√u=3

let x = sqrt u

then
x^2 - 2 x = 3
x^2 - 2 x - 3 = -
(x-3)(x+1) = 0
x = 3 or x = -1
try sqrt u = 3 then u = 9
9 - 6 = 3 Yes
try sqrt u = -3 , that is an imaginary number, forget it
so
u = 9

To solve the equation u - 2√2 = 3, we need to isolate the variable u. Here's the step-by-step process:

Step 1: Start with the given equation: u - 2√2 = 3.

Step 2: Add 2√2 to both sides of the equation to eliminate the term on the left side: u - 2√2 + 2√2 = 3 + 2√2.

Simplifying, u's coefficient is 1, and on the left side the -2√2 and +2√2 cancel out, leaving just u: u = 3 + 2√2.

Therefore, the solution to the equation u - 2√2 = 3 is u = 3 + 2√2.