Lila did it correctly. The answer is 324
Following PEMDAS, we first focus on the parenthesis. So we simplify 9-3 to get 6
So we go from
18*4^2+(9-3)^2
to
18*4^2+6^2
The next step is applying exponents. In this case, squaring the terms, so we go from
18*4^2+6^2
to
18*16+36
Next is multiplying
18*16+36
turns into
288+36
Finally, add up 288 and 36 to get 288+36 = 324
That confirms that Lila is correct
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The error that Rob made is that he computed 18*4^2+9^2-3^2 but it is NOT correct. Saying (x-y)^2 = x^2-y^2 isn't a true equation for all x and y. Again you have to simplify what is in the parenthesis first, and then you can square it. Or you must use the FOIL rule to expand out (9-3)^2
You find a point at the intersection of a plane and line.
Answer:
$54
Step-by-step explanation:
An expression for the total cost would be:
1($32) + ($32-$10) = $32 + $22 = $54
Answer:
Number of dimes = 16
Number of quarters = 17
====================================================
Work Shown:
d = number of dimes
q = number of quarters
d+q = 33 coins total, this solves to d = 33-q
10d = value of all the dimes in cents
25q = value of all the quarters in cents
10d+25q = 585 cents total
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Plug in d = 33-q and solve for q
10d+25q = 585
10(33-q) + 25q = 585
330-10q+25q = 585
15q+330 = 585
15q = 585-330
15q = 255
q = 255/15
q = 17
The man has 17 quarters
d = 33-q = 33-17 = 16
He also has 16 dimes.
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Check:
16 dimes + 17 quarters = 33 coins total
16 dimes = 16*10 = 160 cents
17 quarters = 17*25 = 425 cents
160 cents + 425 cents = 585 cents
The answer is confirmed.
To figure this out, you need to figure out what percentage 68 is of 85.
1. Divide 68 by 85 (Divide the % correct by the total number of questions)
2. 68/85 is .8, which is 80%
