a and c both have √x , so they will both be in brackets multiplied by √x.
b is the only term with √y so it will be outside of the brackets.
So the answer will be:
(a - c)√x + b√y
We can check this by expanding the brackets:
(a - c)√x + b√y
= a√x - c√x + b√y
We can rearrange this to get the same original expression:
a√x - c√x + b√y
= a√x + b√y - c√x
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Answer:
Last option: (a - c)√x + b√y