Answer:
we can get 3/2 as the answer
54554/99999. I think I am right but sorry if I am wrong.
1. Let x be the original amount of baseball cards,
2. half of x was lost so x divided by 2.
3. you buy 18 cards to replace some that were lost
4. You can find the awnser by subtracting 18 from 30, which is 12.
5. Now lets remember that half of your cards were lost. meaning that 12 is only half of what you started with.
6. 12 times 2 would be 24.
7. The Awnser is 24
8. To check your work, you can say x=24, 24 divided by 2 is 12, and 12 plus 18 is 30.
Answer:
<h2>14mph</h2>
Step-by-step explanation:
Given the gas mileage for a certain vehicle modeled by the equation m=−0.05x²+3.5x−49 where x is the speed of the vehicle in mph. In order to determine the speed(s) at which the car gets 9 mpg, we will substitute the value of m = 9 into the modeled equation and calculate x as shown;
m = −0.05x²+3.5x−49
when m= 9
9 = −0.05x²+3.5x−49
−0.05x²+3.5x−49 = 9
0.05x²-3.5x+49 = -9
Multiplying through by 100
5x²+350x−4900 = 900
Dividing through by 5;
x²+70x−980 = 180
x²+70x−980 - 180 = 0
x²+70x−1160 = 0
Using the general formula to get x;
a = 1, b = 70, c = -1160
x = -70±√70²-4(1)(-1160)/2
x = -70±√4900+4640)/2
x = -70±(√4900+4640)/2
x = -70±√9540/2
x = -70±97.7/2
x = -70+97.7/2
x = 27.7/2
x = 13.85mph
x ≈ 14 mph
Hence, the speed(s) at which the car gets 9 mpg to the nearest mph is 14mph
