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2 years ago

The square of a certain number plus ten is equal to 81

Mathematics

1 answer:

Scorpion4ik [409]2 years ago

3 0

Answer:

x = ±8.43 (to 3sf)

Step-by-step explanation:

Let this number be x.

x² + 10 = 81

x² = 81 - 10

= 71

x = ±√71

= ±8.43 (to 3sf)

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See below

Step-by-step explanation:

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write in same form from A

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3 years ago

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The square of a certain number plus ten is equal to 81​

The square of a certain number plus ten is equal to 81