Question

Solve the equation x – 6 =18/x and find the roots correct to one place of decimal.

Answer 1

Therefore 8.2 and -2.2 are the roots of correct to one place of decimal.

question : Solve the equation x – 6 = 18/x and find the roots correct to one place of decima

solution : x - 6 = 18/x

⇒x - 18/x - 6 = 0

⇒x² - 18 - 6x = 0

⇒x² - 6x - 18 = 0

using formula, x = {a ± √(b² - 4ac)}/2a

so, x = {6 ± √(6² + 4 × 18)}/2 × 1

= {6 ± √(36 + 72)}/2

= (6 ± √108)/2

= (6 ± 6√3)/2

= 3 ± 3√3

using √3 = 1.732

so, x = (3 + 3 × 1.732) = 8.196 ≈ 8.2

x = (3 - 3 × 1.732) = -2.196 ≈ -2.2

Therefore 8.2 and -2.2 are the roots of correct to one place of decimal.