For the first question the answer would be the first quadrant
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Multiply (or distribute) the exponent outside the parenthesis with every exponent inside the parenthesis, remember that if there is no exponent shown, then the exponent is 1. Step 3: Apply the Negative Exponent Rule. Negative exponents in the numerator get moved to the denominator and become positive exponents.
let h= history books
science books = s
h=2s there are 2 times as many history as science so to get them equal we double the science
h+s=81 there are 81 total history and science books
2s+s=81 substitute 2s for h in the above equation
3s = 81 combine like terms
s = 27
There are 27 science books
h=2s
h=2(27)
h=54
there are 54 history books
