Use the technique of completing the square to transform the quadratic equation into the form (x + c)^2 = a.

Question

Question1. 6x^2 – 36x + 42 = 0 Question2. 3x^2 – 48x + 153 = 0

Answer 1

Hi Riley,

 

1) 6x^2 – 36x + 42 = 0

Divide by 6 to make the leading coefficient 1.

x^2 - 6x + 7 = 0

Move the constant to the other side of the equation.

x^2 - 6x = -7

Now add the square of half of coefficient b to both sides.

b = -6

x^2 - 6x + (-6/2)^2 = 7 + (-6/2)^2

x^2 - 6x + 9 = 16

(x - 3)^2 = 16

 

With this knowledge, can you answer the second question?