Question

Complete the square. 2x squared +8x-3=0

Answer 1

I hope this helps you


ax^2+bx+c=0


disctirminant = b^2-4ac


x1,2= -b (+,-) square root of disctirminant/2a


2x^2+8x-3=0


a= 2 b= 8 c= -3


disctirminant =8^2-4.2. (-3)


disctirminant = 64+24


disctirminant = 88


square root of 88= 2 square root of 22



x1= -8+square root of 88/2.2



x1= square root of 22-4/2



x2= -8- square root of 88/2.2



x2= -4- square root of 22/2

Answer 2

2x^2 - 8x - 3 = 0

Divide out the 2

x^2 - 4x - 3/2 = 0

Move constant to the other side

x^2 - 4x = 3/2

Half and square -4 and add to both sides

x^2 - 4x + 4 = 3/2 + 4

Write left side as a square, simplify the right

(x - 2)^2 = 22/4

Take the square root

x - 2 = +/- SQRT(22) / 2

Add 2

x = 2 +/- SQRT(22) / 2