Question

Solve the quadratic equation 3x - 9x + 1 = 0

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Give your answers to 3 significant figures.

Answer 1

It should be 3x^2-9x+1=0

`\\ \sf\longmapsto x=(-b\pm√(b^2-4ac))/(2a)`

`\\ \sf\longmapsto x=(9\pm√(81-12))/(2(3))`

`\\ \sf\longmapsto x=\sqrt{9\pm√(69)}{6}`

Answer 2

Answer: 2.88 or 0.116

Explanation:

use the formula: (-b+-√b² - 4 * a * c ) / 2a

here b = -9 , a = 3 , c = 1

so putting the values in our equation,

--9-√(- 9)²-4 * 3 * 1 / 2 * 3 or --9-√(- 9)²-4 * 3 * 1 / 2 * 3

Answer in fraction : (9 +√69 ) / 6 or (9 -√69 )

Answer in decimals : 2.88 or 0.116