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3 years ago

2. Solve. x2 - 72 = 0

Mathematics

2 answers:

Effectus [21]3 years ago

7 0

Answer:

x = ± 6 $\sqrt{2}$

Step-by-step explanation:

Given

x² - 72 = 0 ( add 72 to both sides )

x² = 72 ( take the square root of both sides )

x = ± $\sqrt{72}$ = ± $\sqrt{36(2)}$ = ± 6 $\sqrt{2}$

Butoxors [25]3 years ago

7 0

x² - 72 = 0

x² = 72

x = √72

x = √2×36

x = √2×6²

x1 = 6√2

x2 = - 6√2

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