Use a² − b² to evaluate (87)^2 - (13)^2/74.

100. a² − b² = (a + b)(a − b) = (87 + 13)(87 − 13) = 100 × 74. Dividing by 74 gives 100.

Use $a^{2} - b^{2}$ to evaluate $\frac{( 87 ) ^{2} - ( 13 ) ^{2}}{74}$ .

Competition practiceAlgebra

a^{2} - b^{2} = (a + b) (a - b) = (87 + 13) (87 - 13) = 100 \times 74

. Dividing by 74 gives 100.

Answer: A) 100

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