For quadratics, these formulas are used mainly for factoring.
Your equation can be written as ...
... 2(x² +2x -3) = 0
You factor this by looking for factors of -3 (c=x1·x2) that add to give +2 (b=-(x1+x2)). These are {-1, +3}, so the factorization is ...
... 2(x -1)(x +3) = 0
The roots are then 1 and -3, which sum to -b = -2.
(You will note that the numbers used in the binomial factors are the opposites of the roots x1 and x2 in the Viete's Formulas. That is how we can look for them to sum to "b", rather than "-b".)
V=πr2hWhen r=radius and h=height
Answer:
36 km/h
Step-by-step explanation:
Answer:
The demonstration is showed below
Step-by-step explanation:
The distance betwenn two points is given by:
If the point is equidistant from a point and a line, the distance must be equal. For the line let's select the point (x,-4), because the distance will be ortogonal, and is the small distance between a point and a line. So:
Removing the squares:
(x-2)² + y² = (y+4)²
(x-2)² + y² = y² + 8y + 16
y² - y² - 8y = 16 - (x-2)²
8y = (x-2)² - 16
y = (1/8)*(x-2)² - 16/8
y = (1/8)*(x-2)² - 2