3 years ago

8 The square of a number is 12 less than 7 times the number. What is the number?

Mathematics

1 answer:

Alex3 years ago

8 0

7x^2 - 12 = 0
7x^2 = 12 | : 7
x^2 = 12/7 | sqrt
x = sqrt(12/7)
x = sqrt(84) / 7
x = 2sqrt(21) / 7

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