Question

Solve the quadratic equation 5x² -8x-4=0 by the method of completing the square​

Answer 1

Step-by-step explanation:

5x² - 8x - 4 = 0

=> 5x² - 8x = 4

=> x² - 8/5 x = 4/5 [ divide both sides with 5 ]

=> x² - 8/5 x + (4/5)² = 4/5 + (4/5)²

[ take half the coefficient of x , square it and add it to both sides of the equation ]

=> x² - 8/5 x + (4/5)² = 4/5 + 16/25

=> (x - 4/5)² = (20 + 36) / 25

=> (x - 4/5)² = 36/25

=> x - 4/5 = ±6/5 [ taking square root on both sides ]

=> x = 6/5 + 4/5 = 10/5 = 2

=> x = -6/5 + 4/5 = -2/5

therefore x = 2 and x = -2/5

Answer 2

Answer:

The equation is a linear equation in one variable. It can be solved by the transposing method. Therefore x = 3 + 19 5 and x = 3 − 19 5 are the roots of the quadratic equation. Thus, the quadratic equation 5 x 2 − 6 x − 2 = 0 is solved by the method of Completing the square