Simplify:
−3=12y−5(2y−7)
−3=12y+(−5)(2y)+(−5)(−7)(Distribute)
−3=12y+−10y+35
−3=(12y+−10y)+(35)(Combine Like Terms)
−3=2y+35
Flip the equation.
2y+35=−3
Subtract 35 from both sides.
2y+35−35=−3−35
2y=−38
Divide both sides by 2.
2y/2=−38/2
y=−19
Answer:
the answer to the question is "C"
Find two points on the graph that the line crosses through almost perfectly. It looks like (1,10) and (9,1) will do.
Use them to compute the slope:
m = (1 - 10) / (9 - 1)
= -9/8
Then set up the "point-slope form":
y - y0 = m * (x - x0)
You choose some point (x0, y0) that the line crosses through. We already know the line passes through (1,10) pretty well, so let's use that.
x0 = 1
y0 = 10
Now finish plugging into the equation:
y - 10 = -9/8 * (x - 1)
The above equation will work fine for an answer, but let's go a step further and solve for y.
y - 10 = -9/8x + 9/8
y = -9/8x + 9/8 + 10
y = -9/8x + 9/8 + 80/8
y = -9/8x + (9 + 80)/8
y = -9/8x + 89/8
You haven't told me what the question is. But I put the mouse
to my forehead, closed my eyes, took a deep breath, and I could
see it shimmering in my mind's eye. It was quite fuzzy, but I think
the question is
"What score does Andrew need on the next test
in order to raise his average to 72% ?"
The whole experience drew an incredible amount of energy
out of me, and the mouse is a total wreck. So we'll just go ahead
and answer that one. I hope it's the correct question.
The average score on 4 tests is
(1/4) (the sum of all the scores) .
In order for Andrew to have a 72% average on 4 tests,
the sum of the 4 scores must be
(4) x (72%) = 288% .
Out of that total that he needs, he already has
(64% + 69% + 73%) = 206%
on the first three tests.
So in order to average 72% for all 4 tests,
he'll need to score
(288% - 206%) = 82%
on the fourth one.
Answer:
Due to the higher z-score, he did better on the SAT.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Determine which test the student did better on.
He did better on whichever test he had the higher z-score.
SAT:
Scored 1070, so 
SAT scores have a mean of 950 and a standard deviation of 155. This means that 
.
ACT:
Scored 25, so 
ACT scores have a mean of 22 and a standard deviation of 4. This means that 
Due to the higher z-score, he did better on the SAT.
