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Algebra Difficulty 1.3 Junior Find the answer

Simplify the expression (100+9)×(100−9)(\sqrt{100}+\sqrt{9}) \times(\sqrt{100}-\sqrt{9}).

A number or a short expression. Spacing and $ signs are ignored.

Solution

Simplifying, (100+9)×(100−9)=(10+3)×(10−3)=13×7=91(\sqrt{100}+\sqrt{9}) \times(\sqrt{100}-\sqrt{9})=(10+3) \times(10-3)=13 \times 7=91.

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