This equation can be used when comparing ages.
An example to illustrate this:
Assume that adding 6 to 3 times the age of Jack will give us the age of his grandfather.
When translating this into equations, assuming that the age of jack is "a" and the age of his grandfather is "b", we will find that:
b = 6 + 3a
Since the area of a triangle is in the form
area=0.5(base)(height)
height=base+7
let base=x
area=0.5(x)(7+x)
30=3.5x+0.5x^2
multiply the equation by 2
60=7x+x^2
subtract 60 from both sides
x^2+7x-60=0
(x-5)(x+12)=0
thus x=5 or x=-12 since we are only considering positive answers
x=-12 is rejected
so base=5 and height=5+7=12
We begin with 1,000 fish in a lake.
Each year the population declines to 15%
Then they put back 500 fish in the lake.
The equation: (1000 * .85) +500
Degree 4 means you'll have x^4 as your leading term. Multiplicity of 3 means you have the same factor 3 times. So if x = -2, then (x + 2) = 0, so (x + 2) is used 3 times. FOIL that out 3 times and you get x^3 + 6x^2 + 12x + 8. Now multiply by (x + 0) to get a 4th degree polynomial of x^4 + 6x^3 + 12x^2 + 8x. There!