For these kinds of expressions use FOIL (first, outside, inside, last).
-2x • 9x = -18x^2
-2x • -3y = 6xy
8y • 9x = 72 xy
8y • -3y = -24y^2
Now combine them all:
-18x^2 + 78xy - 24y^2
Answer:
Year = 1995 and population = 315
Year = 2015 and population = 715
Step-by-step explanation:
It is given that the population of two different villages is modeled by the given equations:
The population of both villages are same after x years after 1980 if
Splitting the middle term, we get
It means, after 15 or 35 years, the population will same.
For x=15, years is
and population is
For x=35, years is
and population is
.
Therefore, population are equation in Year = 1995 and population = 315 or Year = 2015 and population = 715.
Part A: (n^2-6n)+16
[(n^2-6n+9)-9]+16
(n-3)^2+7
Part B: From the above result,
Vertex (3,7) this is the minimum point of the graph since the coefficient of a is positive
Part C: The axis of symmetry is basically the x coordinate of the vertex, so the axis of symmetry is x=3
Hope this helps!
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