Answer: 
Step-by-step explanation:
The equation of the line in Slope-Intercept form is:

Where "m" is the slope and "b" is the y-intercept.
You need to find slope of the line with the formula:

Pick to points of the given line. You can choose the point (60,3) and the point (30,2).
Then, substituting into the formula:

You can observe in the graph that the line intercepts the y-axis at the point (0,1), therefore "b" is:

Substituting the slope and the y-intercept found into
, you get the equation of this line:

Where "y" represents the Height (1,000 ft) and "x" represents the Time in seconds.
8x^4-28x^3+4x^2
That’s the answer
Note: I'm afraid I can't put the work for the answers, for lack of time =/
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1. 0 or -3
2. 0 or 4
3. -2 or 3
4. 0 or 1/2
5. -2 or 3
6. 0 or 5
7. 0 or 7
8. 0 or -2
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9. Substitute 0 for h in "h = -16x^2 + 16x" then solve for x
0 = -16x^2 + 16x
<span>Subtract -16x^2+16x from both sides.
</span><span>0−<span>(<span><span>−<span>16x2</span></span>+16x</span>)</span></span>=<span><span><span>−<span>16<span>x2</span></span></span>+<span>16x</span></span>−<span>(<span><span>−<span>16x2</span></span>+16x</span>)
</span></span><span><span>16<span>x2</span></span>−<span>16x</span></span>=<span>0
</span>
Factor the left side of the equation
<span><span>16x</span><span>(<span>x−1</span>)</span></span>=<span>0
</span>
Set factors to equal 0
<span><span>16x</span>=<span><span><span>0<span> or </span></span>x</span>−1</span></span>=<span>0
</span>x = 0 or x = 1
Answer:
Total number of virus after 7yrs= 247484.7 virus
Step-by-step explanation:
Total number of virus after 7yrs = 2573(1+0.92)⁷ = 247484.7 virus