a = 4, b = -21, c = -18
to keep from getting "mixed up", evaluate the discriminant first ...
b<sup>2</sup> - 4ac = (-21)<sup>2</sup> - 4(4)(-18) = 729
sqrt(729) = 27
x = (21 +/- 27)/8
x = -3/4, x = 6
since the discriminant is a perfect square, the original quadratic will factor ...
4x<sup>2</sup> - 21x - 18 = 0
(4x + 3)(x - 6) = 0
x = -3/4, x = 6
Answer:
x = - 4 ± 2
Step-by-step explanation:
Given
f(x) = x² + 8x + 4
To find the zeros let f(x) = 0, that is
x² + 8x + 4 = 0 ( subtract 4 from both sides )
x² + 8x = - 4
To solve using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(4)x + 16 = - 4 + 16
(x + 4)² = 12 ( take the square root of both sides )
x + 4 = ± 
= ± 2 ( subtract 4 from both sides )
x = - 4 ± 2
Thus the zeros are
x = - 4 - 2 and x = - 4 + 2
Answer:
4,000 meters
Step-by-step explanation:
The conversion from kilometers to meters is 1 kilometer equals 1,000 meters. So times the conversion by 4 to get 4,000 meters.
The first one because it has a negative slope (which is -4) and h is always the opposite while k stays the same. By the way h is the 2 and k is the 3
