It should be written in the form ax²+bx+c=0,
so you meed to move -8 to the left side
2x²+6x+8=0
the number in front of x² is a
the number in front of x is b
the number without x is c,
so a=2, b=6,c=8
Answer:
See the explanation below.
Step-by-step explanation:
Percentage of all the students landing point up 
Percentage of student ten landing point up 
Required Difference 

a.
b.
The metal obey this law for values of strain until 0.05, where we have a linear relationship (each increase of 0.01 in the strain causes an increase of 100 in the stress). After this point, we don't have a linear relationship anymore.
c. Since an increase of 0.01 in the strain causes an increase of 100 in the stress, the slope is:

Now, calculating the coefficient b (y-intercept), we have:

So the equation is:

d.
The maximum value of stress is 560, and occurs at strain = 0.07.
This can be expressed as exponential growth of the form:
f=ir^t, f=final amount, i=initial amount, r=common ratio (rate), t=time
In this case we are given the point (2, 6500) and i=5000 so we can solve for the rate...
6500=5000r^2 divide both sides by 5000
1.3=r^2 take the square root of both sides and note that we know r>0
r=1.3^(1/2) so our equation becomes:
f=5000(1.3)^(1/2)^t and knowing that (a^b)^c=a^(b*c) we can say:
f=5000(1.3)^(t/2) so for t=18
f=5000(1.3)^9
f≈53022 (to nearest whole bacteria)
Plotting the data to get the line of best fit, it is:
y<span> = 0.087</span>x<span> + 0.587
substitute x=2030-1980=50,
y = $4.94 is the price in 2030</span>