The presence of which type of intercellular connections between endothelial cells of brain capillaries results in the blood–brain barrier?.

the correct answer: the index of refraction of the second medium is lower i tried this persons answer and it was wrong this person is lying

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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