C because that with the that is that
Answer:
(x-1)(x-9)
Step-by-step explanation:
Answer:
r = 225 Mil/h speed of the airplane in still air
Step-by-step explanation:
Then:
d is traveled distance and r the speed of the airplane in still air
so the first equation is for a 4 hours trip
as d = v*t
d = 4 * ( r + 25) (1) the speed of tail wind (25 mil/h)
Second equation the trip back in 5 hours
d = 5 * ( r - 25 ) (2)
So we got a system of two equation and two unknown variables d and
r
We solve it by subtitution
from equation (1) d = 4r + 100
plugging in equation 2
4r + 100 = 5r - 125 ⇒ -r = -225 ⇒ r = 225 Mil/h
And distance is :
d = 4*r + 100 ⇒ d = 4 * ( 225) + 100
d = 900 + 100
d = 1000 miles
Well if she added three blue and four red originally, and is now using 16 red then we would divide 16 by the original four. Which means to get the number of blue we are gonna end up multiplying by four. So three times four is twelve. Which means she would use 12 blue and 16 red to get the same color she got with 3 blue and 4 red earlier. The equation, lets use x for blue and y for red, would be 4(3x + 4y) = desired color
Okay so instead of dividing you will cross multiply.
4n(15)=84(5)
60n=420
420/60=7
Answer: n=7