Maria looks straight up and sees an airplane 5 miles above her. The airport runway is exactly 7 miles away from her. What is the best estimate of the distance between the runway and the airplane? A: between 6 and 7 miles
B: between 7 and 8 miles
C: between 8 and 9 miles
D: between 9 and 10 miles

25.3

step-by-step explanation:

1st step

add 3+6

=9

multipy 9*3

=37

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.

for this case we have that by definition, the surface area of a cylinder is given by:

where:

r: it is the radius of the cylinder

h: it is the height of the cylinder

we can also rewrite it as:

where:

la: it's the lateral area

ba: area of the base

option a

hello,

as we don't know if g(x) is continue,

answer b

f(x)=2x²-8x+1=2(x²-4x+4)+1-8=2(x-2)²-7

vertex is (2,-7) ( a minimum since coefficient of x² is > 0)