<u>X - Intercept</u>
f(x) = -x² + 4x - 4
0 = -x² + 4x - 4
x = <u>-(4) +/- √((4)² - 4(-1)(-4))</u>
2(-1)
x = <u>-4 +/- √(16 - 16)</u>
-2
x = <u>-4 +/- √(0)
</u> -2<u>
</u> x = <u>-4 +/- 0
</u> -2<u>
</u> x = <u>-4 + 0</u> x = <u>-4 - 0</u>
-2 -2
x = <u>-4</u> x = <u>-4</u>
-2 -2
x = 2 x = 2
The solution to the problem is {2, 2}, or {2}. The x - intercept of the problem is (2, 0).
<u>Y - Intercept</u>
f(x) = -x² + 4x - 4
f(x) = -(0)² + 4(0) - 4
f(x) = -(0) + 0 - 4
f(x) = -0 + 0 - 4
f(x) = 0 - 4
f(x) = -4
The y - intercept of the problem is (0, -4).
<u />
Answer:
The phone roughly cost 302 dollars
Step-by-step explanation:
10% of 432=43.2
20% of 432=86.4
432-129.6=302.4
Y = x - 1
because the gradient is 1 and the y-intercept is -1
Use this equation: Amount after years=Initial investment*(1+Interest rate/time compounded yearly)^number of years*times compounded yearly
So A=25,000(1+.095/1)^8*1
Simplify
A=25000(1.095)^8
Simplify
A=25000(2.07)
Solve
A=$51,671.73
This equation can be used for all problems of this type.
