The correct answer would be 128.
Hi there! Hopefully this helps!
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It <u>decreased by 30 cents</u> per week.
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The average <em>rate of change</em> is calculated as:
the <u>ratio of the sum of the change</u> in the three weeks <u>divided by</u> <u>the number of weeks. (</u>The <em>number of weeks</em> being <u>3</u>)
<em>Rate of change</em> =
.
(-60 + -10 + -20 = -90). So, to <em>simplify</em> it:
= <u><em>-30</em></u>
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Incase you are confused:
Since the average <u>rate of change</u> is <em>negative</em>, this means that the <u>stock price</u> has <em>decreased</em>.
Answer: (3x + 11y)^2
Demonstration:
The polynomial is a perfect square trinomial, because:
1) √ [9x^2] = 3x
2) √121y^2] = 11y
3) 66xy = 2 *(3x)(11y)
Then it is factored as a square binomial, being the factored expression:
[ 3x + 11y]^2
Now you can verify working backwar, i.e expanding the parenthesis.
Remember that the expansion of a square binomial is:
- square of the first term => (3x)^2 = 9x^2
- double product of first term times second term =>2 (3x)(11y) = 66xy
- square of the second term => (11y)^2 = 121y^2
=> [3x + 11y]^2 = 9x^2 + 66xy + 121y^2, which is the original polynomial.