I think it might be r= -3
<span>The Blackpool Tower took 3 years to build using about 2,500 tons of steel and 5,000,000 bricks. The tower was officially opened to the public in 1894. The architects of the project, Messers Maxwell and Tuke, died before the building was completed.</span>
I think that the answer is $569.8. 550 times 0.072 times 0.5 (half a year) is 19.8, then 550 + 19.8 is 569.8.
1. x
2. x
3. -x^2
4.
5. x
6. x^3
7. x
8. |x|
9. x-2
10. x/3
11. x/2
12. x+2
Let x and (442-x) represent the distance of the trains traveled. X/90 mph=442-x/80 mph
Cross multiply 80×x =90(442-x)
80x=90×442-90x
170x=90×442
X= 90×442/170
X=234, distance traveled by train going 90mph
234mi/90mph = 2.6 hr, time it takes for the two trains tok meet.
Checking your answer:
90×2.6+80×2.6=234mi+208mi = 442mi
