Answer:
19
Step-by-step explanation:
He gets 6 wrong and 19 correct
First you have to factor (aka, multiply) your binomial (which is what you have written) usually it helps to organize your thinking, and help tell what you need to multiply, to use the binomial chicken(or crab claw, what ever you want to call it) which basically you draw two arches, one arch connecting the 3 and 4, and then the other the 3 and 9i. on the opposite side (depending on wheater you connected then from the top or bottom) you connect (with an arch) the 6i and the four, and then the 6i to the 9i.
so now you multiply each piece you've connected:
3 x 4= 12
3 x 9i= 27i
6i x 4= 24i
6i x 9i= 54i^2
after you've done this you can move on to putting it into standard form, which just means you put things in descending order, depending on how many exponents the x (or in this case i) has.
your largest exponent is 54i^2, so that's first in out equation, next 27i, and 24i (you can combine these because they are like term) which equals 51i, after that you just add the 12 on the end, so the final equation looks like this:
54i^2+51i+12
9 miles, you dont even need much math, just common sense. divide 12 by 4 and you get three. multiply 3 by 3 to get 9.
Answer: A. divided the difference of the two quantities by the sum of the two quantities.
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Explanation:
The difference of the quantities is 20-15 = 5
The sum of the quantities is 20+15 = 35
Dividing those results leads to 5/35 = 0.142857 which rounds to 0.1429
That converts to 14.29%
This is likely the path Adam took. This path is incorrect. The correct steps are shown below
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Difference = 20-15 = 5
Divide the difference over the original quantity
5/20 = 1/4 = 0.25 = 25%
We have a 25% decrease because the new quantity (15) is smaller than the old quantity (20)
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Here's another way to approach the problem
A = old value = 20
B = new value = 15
C = percent change
C = [ (B-A)/A ] * 100%
C = [ (15-20)/20 ] * 100%
C = (-5/20)*100%
C = -0.25*100%
C = -25%
The negative C value means we have a negative percent change, ie we have a percent decrease. So this is another way to get a 25% decrease.
