The function f(x) = 4x – 0.1x2 is used to model the curve of
a bridge over a small river, where x is the distance from
one side of the river and the x-axis represents the ground.
The mathematical range for the function is the set of real
numbers

the 8 in 8,420 is in the thousands place so it's value is 8 thousand.

the 8 in 6,870 is in the hundreds place so it's value is 8 hundred.

divide 8000 by 800 to find the answer:

8000 / 800 = 10

the 8 in 8,420 is 10 times greater than the 8 in 6,870

sina-sinb

cosb+cosa

tana-tanb

cos0+cos x pi/3

20tan

step-by-step explanation: