Question

Quadratic Equations :

Solve for x and give your answers correct two decimal places.
a) 4x^2 - 7x + 2 = 0
b)x^2 - 10x + 6 = 0
c) 5x(x + 2) =3

Answer 1

a. x = 1.39 , 0.36

b. 9.36, 0.54

c. x = 0.26, -2.26

Explanation:

a Using the quadratic formula:-

x = [ -(-7) +/- sqrt ((-7)^2 - 4*4*2)) / (2*4)]

= 7 +/- sqrt(17) / 8

= 7/8 +/- sqrt17/8

x = 1.39 , 0.36

b) x = - (-10) +/- sqrt (100 - 4*1*6) / 2

= 5 +/- sqrt 76 / 2

= 9.36, 0.54

c) 5x(x + 2) = 3

5x^2 + 10x - 3 = 0

x = [-10 +/- sqrt(4*5*-3)] / 10

x = 0.26, -2.26