The answer is never, that is, on a 2 dimensional plane. You can perform an experiment to see why it is the case. On curved surfaces though, two lines can intersect one another more than once. For instance, on the surface of planet Earth, two lines can intersect one another, both at the Earth's North Pole and South Pole.
Find the common ratio for the following sequence. 27, 9, 3, 1, ... = 1/3
Find the common ratio for the following sequence. 1/2, -1/4, 1/8, -1/16, ... = -1/2
Find the common ratio for the following sequence. 1/2, -1/4, 1/8, -1/16, ...
= -1/2
Answer: C) Find the factors of c that add up to b.
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Explanation:
If we want to factor something in the form x^2+bx+c, then we look for two numbers that
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Let's look at a specific example
Consider factoring x^2+5x+6
We need to find two numbers that...
- Multiply to c = 6
- Add to b = 5
Through trial and error, you should find the two numbers to be 3 and 2. This means it factors to (x+3)(x+2). The order of the factors doesn't matter.
You can use the FOIL rule or the box method to expand out (x+3)(x+2). You should get x^2+5x+6 again.
