Answer:
{-1, 5} (two real solutions).
Step-by-step explanation:
On the left side we want x^2, not x?
We need to rewrite x? = 4x - 5 in standard form, that is, as a quadratic with x terms in decreasing powers of x:
x^2 - 4x + 5 = 0
This factors easily to (x - 5)(x + 1) = 0.
We let each factor equal zero (0) separately and solve for x:
{-1, 5} (two real solutions).
Let x equal Thomas' age. Then Huilan's age is 2x. Set up an equation to model this situation:
x+2x=78
<em>*Combine like terms*</em>
3x=78
<em>*Divide both sides by 3*</em>
x=26
Hope this helps!!
Answer:

C is correct.
Step-by-step explanation:
At a picnic,
Number of adults is 3 times as number of children.
Number of women is twice as number of men.
Total number of men, women and children at the picnic be x
Let number of children be c
Let number of men be m
Let number of women be w
# Number of women is twice as number of men, w = 2m
# Number of adults is 3 times as number of children, w + m = 3c
2m + m = 3c (∴ w=2m )
c = m
Total number of men, women and children at the picnic be x
∵ c + m + w = x
m + m + 2m = x
4m = x
Number of men, 
Hence, The total number of men will be 
Answer: Choice C
They should be blocked by pain resistance so the subjects are as similar as possible.
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Explanation:
The process of blocking in statistics is where we group up people in blocks, and each block is determined by a characteristic of some sort. In this case, we're grouping people up by pain resistance level. Those very resistant to pain will be in one group, while those who easily feel pain will be in another block, and so on. It might be effective to have a pain scale and sort people by that.
Blocking is done so that we eliminate unwanted variability. We are testing the effectiveness of the itching cream, so all we care about is if the itch reduces or not. We aren't worried about the levels of pain. However, it says that "Previous studies have shown the effects of treatment may vary based on a subject's pain resistance". So we group up the people by pain tolerance to help eliminate the variability of pain tolerance levels.
This is why choice C is the final answer.
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Extra info:
- Choice A is false because a person's name doesn't have anything to do with if the treatment works or not.
- Choice B is false because we weren't given any info to indicate it being true. It may be true, but we simply don't have enough info to confirm it.
- Choice C is false for similar reasons as choice B.
A coyote had 10 pups in her third litter. (10)
It was twice as many as in her second litter,( 2( second litter) = third litter
her second litter had 3 more pups than her first.( first litter +3)=2nd litter
Find the number of pups in her litter