Vectors simple physics help please

You’re supposed to find this
Given this

Here’s what I did, is my answer correct ?

We need to see the question and your working to help you.

everything is uploaded now

Was the diagram given to you? How does A = B or do you mean the magnitude is equal?

Only magnitude yes

Sorry I really can't follow what you are trying to do here.

Find the magnitude of the 1st picture given in the info in the 2nd picture. This is exactly how we were given the question in the quiz.
The magnitude of A= that of B
There’s a 45 degree angle between them and A is parallel to the x axis.

Your general method looks fine - pythagoras on the "x" and "y" components - except for the same error in each part:

$(A+A\cos 45)^2=???$

Oh , ?

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