Both are correct they just chose a different variable to solve for first. they will both get correct answers if they do the rest correctly.
Answer:
80cm^2
Step-by-step explanation:
20*5=100
10*2=20
100-20=80
Answer:
Step-by-step explanation:
LOL The graph doesn’t match the y intercept :)
Anyway
If we have point (0,-3) we have a quadratic of
y=ax^2+bx-3 we are given points (-1,0) and (2,0) so
a-b-3=0 and 4a+2b-3=0
4a+2b-3+2(a-b-3)=0
4a+2b-3+2a-2b-6=0
6a-9=0
6a=9
a=1.5, since a-b=3
1.5-b=3
b=-1.5
y=1.5x^2-1.5x-3
9514 1404 393
Answer:
21.25 seconds
Step-by-step explanation:
In miles per second, the speed of the jet is ...
(720 mi/h)/(3600 s/h) = 1/5 mi/s
The speed of the sound is the same:
(1 mi)/(5 s) = 1/5 mi/s
Then the rate of closure between the airplane and the sound is ...
(1/5 mi/s) +(1/5 mi/s) = 2/5 mi/s
To find the time required to close a gap of 8 1/2 miles, we can use the relation ...
time = distance/speed
time = (8.5 mi)/(0.4 mi/s) = 21.25 s
The pilot will hear the thunder 21.25 seconds after the flash.