The area under the speed curve tells you how much distance the vehicle covers.
The distance for first 30 s corresponds to the area of a rectangle with height <em>k</em> m/s and length 30 s, or
(<em>k</em> m/s) (30 s) = 30<em>k</em> m
The distance for the last 20 s corresponds to the area of triangle with height <em>k</em> m/s and length 20 s, or
1/2 (<em>k</em> m/s) (20 s) = 10<em>k</em> m
If the total distance traveled was 1.7 km = 1700 m, then
30<em>k</em> + 10<em>k</em> = 1700
40<em>k</em> = 1700
<em>k</em> = 42.5
Replace F(x) with y
y=x^3-10x^2+24x
To find the roots replace y with 0.
0=x^3-10x^2-24x
Rewrite the equation as
x^3-10x^2+24x=0
Factor the left side
x(x-6)(x-4)=0
The solution is a result of
x=0, x-6=0, and x-4=0
The answer is:
x=0, 6, 4
<h3>
Answer: a < 14 (Choice B)</h3>
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Explanation:
Add 4 to both sides
a-4 < 10
a-4+4 < 10+4
a < 14
The reason why we add 4 to both sides is to undo the "minus 4" that's happening to the variable.
-4/4 can be reduced to -2.
(-8/4) can be reduced to -1.
What you have to do next is to add -1-(-2).
The final answer is 1.
Hope that helps!!!.
