My teacher said

If x-2(square root xy)=9-4(square root 2)
so since there are two square roots
-2(square root xy) equals -4(square root 2)

How is this possible, could the values be different and they are not equal.

1 answer

your teacher is dead wrong.

example:

6-sqrt25=15-sqrt196
sqrt25 is not equal to sqrt196, ever.
Point this out to your teacher.
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