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2 years ago

12

Solve x^2-4=77 E2020

2 answers:

Natali [406]2 years ago

7 0

Answer:

x = 9 or x = -9

Step-by-step explanation:

x² - 4 = 77

then

x² - 4 + 4 = 77 + 4

then

x² = 81

then

x² - 81 = 0

then

x² - 9² = 0

then

(x - 9)(x + 9) = 0

then

x - 9 = 0 or x + 9 = 0

then

x = 9 or x = -9

__________________________

:)

Oxana [17]2 years ago

3 0

Answer:

Step-by-step explanation:

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Answer:

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