A is the answer I hope e2020 is going good for you
Answer:
The given equation is -2x^2 = -8x + 8
This can be rewritten as 2x^2 - 8x + 8 = 0
Here the value of a =2, b = -8 and c = 8
Discriminant = b^2 - 4ac
Now plug in the above values in the discriminant, we get
= (-8)^2 - 4*2*8
= 64 - 64
= 0
Here the discriminant is 0, so we will get one real root.
The discriminant is equal to 0, which means the equation has one real number solution.
Hope this will helpful.
Thank you.
Answer:
B: The mean study time of students in Class B is less than students in Class A.
Step-by-step explanation:
To find out why answer B is the right answer, I will give you facts from each option.
Option A is false. <em>The mean study time in Class A is 4.8. Meanwhile in Class B it is 4. For Class A, sum up the 20 study times which is 96 and divide them by 20, you will get 4.8 hours of mean study time. For Class B, the sum of the 20 study times is 80, which divided by 20 will be 4.
</em>
Option B is True. <em>See previous explanation.
</em>
Option C is False. <em>The median study time in Class B is 4. The median study time in Class A is 4.8,
</em>
Option D is False. <em>The range in Class A is from 2 to 8. The range in Class B is from 2 to 7.
</em>
Option E is False: <em>The mean and median study time of these classes is different.</em>
Change each mixed fraction to improper
3 2/5 = 15/5 + 2/5 = 17/5
9 1/10 = 90/10 + 1/10 = 91/10
Find a common denominator. Multiply 2 to both numerator and denominator of 17/5
17/5(2/2) = 34/10
34/10 + 91/10 = 125/10
125/10
Simplify. Divide
125/10 = 12.5
12.5 is your answer
hope this helps
Guppies: u
Goldfish: o
3 times as many guppies as goldfish
3*o = u (there are more guppies than goldfish)
o + u = 20
o = 20 - u
Substitute in (20 - u) for o in the first equation and solve:
3* (20 - u) = u
60 - 3u = u
60 = 4u
u = 15
He has 15 guppies. Then substitute in the number of guppies into either equation to find the number of goldfish:
o + u = 20
o + (15) = 20
o = 5
Hope this helps! :)