Answer:
21.42
Step-by-step explanation:
Imagine it as a full circle. 3 x 4 will give you the diameter of a full circle, which is 12. circumference = pi x diameter. so 12 pi (we can work that out later). now for the quater circle, divide it by 4, so 3 pi. Then you have the 2 extra edges which are both 2r, so 6 each. finally, you have 3 pi plus 12 which = 21.42
Here you go!! I hope my answer assists you in the future as well!! :))
Since we need to find the point at which the 2 lines intersect at the x-axis, we need to find where the 2nd line intersects the x axis, by plugging in y=0.
x-2(0)=4
x=4
Therefore, at (4,0).
Now we plug in (4,0) at the first equation.
4b+3(0)=10
4b=10
b=5/2
Therefore, at b=5/2
14 million bacteria were present when the antibiotic was first introduced.