Solve x2 + 8x − 3 = 0 using the completing-the-square method. x = four plus or minus the square root of three
x = negative four plus or minus the square root of three
x = four plus or minus the square root of nineteen
x = negative four plus or minus the square root of nineteen

Step-by-step explanation:

x^2+8x-3=0 (move constant to other side by adding 3 to each side)

x^2+8x=3 (halve thr linear coefficient, square it and add to each side, (8/2)^2=16)

x^2+8x+16=3+16 (now the left side is a perfect square)

(x+4)^2=19 (now take the square root of each side)

x+4=+-(19^(1/2)) (finally subtract the constant to isolate x by itself)

x= -4+-(19^(1/2))

x=negative four plus or minus the square root of nineteen