Step-by-step explanation:
h = -490t² + 1470t
When h = 980:
980 = -490t² + 1470t
Simplifying:
0 = -490t² + 1470t - 980
0 = t² - 3t + 2
Factoring:
0 = (t - 1) (t - 2)
t = 1, 2
There are two solutions because the rocket first reaches the height of 980 cm as it's going up at 1 second, then it reaches that height again as it's coming down at 2 seconds.
Answer:
9ab/8
Step-by-step explanation:
-3/4 a * -3/2 b
negative time negative is positive
3*3/(4*2) ab
9ab/8
we can make the number a mixed number but it is not usually done
(1 1/8 ) * ab
0.805 mph
divide speed value by 44.704
Area of chalkboard = 4 feet x 6 feet = 24 square feet.
Total cost = 24 square feet x $7.21 per square foot = $173.04
Answer: $173.04
Answer:
The mean absolute deviation of seven is 10
Step-by-step explanation:
