9514 1404 393
Answer:
Step-by-step explanation:
We notice the first pair of coefficients is the same as the last pair (with the sign changed). This means we can factor by grouping.
f(x) = (2x^3 +6x^2) -(2x +6)
f(x) = 2x^2(x +3) -2(x +3)
f(x) = 2(x^2 -1)(x +3) = 2(x -1)(x +1)(x +3)
The factors are made to be zero when x is 1, -1, or -3.
The x-intercepts are (1, 0), (-1, 0), (-3, 0).
The y-intercept is the constant, -6.
a.
Sally has $28.00 in her bank account and starts saving $18.25 every week.
Let x represent the number of weeks from when he have $28.00 in her account.
and y represent the amount in her account at week x;
We can write the function of the case as;
where m is the amount she saves every week, and b the initial amount in her account.
So, the function will be;
b.
Her friend Suzy has $161.00 in her bank account and is withdrawing $15 every week.
Using the same rule as in a above;
The function will be;
c.
The graph of the two functions is shown below;
d.
The point where the two lines intersect is shown in the graph above.
The point is at;
Which is at week 4 and balance $101.
e.
The point at which they intersect is the point where they both have the same values.
It is the week when both Sally and Suzy have the same amount in there account.
So, at the fourth week (week 4) Sally and Suzy both have $101 in their account
