Answer:
x ≈ - 4.12 , x ≈ 0.12
Step-by-step explanation:
Given
2x² + 8x - 1 = 0 ( add 1 to both sides )
2x² + 8x = 1 ← factor out 2 on the left side
2(x² + 4x) = 1
To complete the square
add/ subtract (half the coefficient of the x- term )² to x² + 4x
2(x² + 2(2)x + 4 - 4) = 1, that is
2(x + 2)² - 8 = 1 ( add 8 to both sides )
2(x + 2)² = 9 ( divide both sides by 2 )
(x + 2)² =
( take the square root of both sides )
x + 2 = ±
= ±
= ±
( subtract 2 from both sides )
x = - 2 ± 1.5
, thus
x = - 2 - 1.5
≈ - 4.12 ( to 2 dec. places )
x = - 2 + 1.5
≈ 0.12 ( to 2 dec. places )
Answer:
a
Step-by-step explanation:
Answer:
4th option
Step-by-step explanation:
x² - 2x - 3 = 0 ( add 3 to both sides )
x² - 2x = 3
using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 1)x + 1 = 3 + 1
(x - 1)² = 4
Y = x - 6
Please let me know if you need explanation.
Answer:
-33/10 or -3.3
Step-by-step explanation: