Y = x² + 2x
When x=2, you want to go through the equation, and wherever you see ' x ',
write ' 2 ' in that place instead. When you do that, it'll say ...
Y = 2² + 2(2)
Now, to clean it up and make it less complicated,
you have to remember that
2² = 4 and 2(2) = also 4 . Write those in the equation:
Y = 4 + 4
Now you have to know what (4 + 4) is.
You can work it out using your fingers, or small stones, or pennies.
(4 + 4) = 8 . Write THAT in the equation, and now it says
Y = 8 .
That's the answer.