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2 years ago

Please help me with this question.

Mathematics

2 answers:

dangina [55]2 years ago

8 0

Answer:

a. 1.5 inches wide.

Step-by-step explanation:

If the width of the frame is x the length of the picture + frame = 2x + 12 and the width is 2x + 9 , so we have the following equation:

The total area = (2x + 9)(2x + 12) = 180

4x^2 + 24x + 18x + 108 = 180

4x^2 + 42x - 72 = 0

2(2x^2 + 21x - 36) = 0

2 (2x - 3 )(x + 12) = 0

x = 1.5 , -12 (we ignore the negative root).

igomit [66]2 years ago

7 0

The correct answer is “a”

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This is my last question by the way

Leni [432]

Part A:

There are 25 blocks for the length, and the length of each is 5.5 inches. 5.5x25=137.5

There are 9 blocks for the height, and each is 2.75 inches. 2.75x9=24.75

Since we're trying to find how much longer the length is to the width, we find the difference. 137.5-24.75=112.75

So part A answer is 112.75 (or 112¾)

Part B:

We know the length is 137.5 and the height is 24.75. To find how many times longer the length is, we need to divide to see how many 24.75 can go into 137.5.

137.5÷24.75=5.55

So the answer to part B is 5.55. Given the context, the answer would probably be 5, because that's how many entire height can fit.

Sorry if it's wrong lol

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2 years ago

Ana has 5 muffins but 8 friends coming over. How much will each friend get?

maw [93]

1.6

Step-by-step explanation:

7 0

3 years ago

Read 2 more answers

Ieda and Thanh both offer piano lessons. Ieda charges an initial fee of $8.50 and an hourly rate of $11.00. Thanh charges an ini

Trava [24]

The price for each instructor will be the same at 3 hours. How I determined this answer:

First off, you need to add the initial price and hourly price for each person together, so you already know how much it will cost for 1 hour, including the initial fee. Here's how you do it:

Ieda: $11.00 (hourly price) + $8.50 (initial fee) = $19.50 (for 1 hour)

Thanh: $10.50 (hourly price) + $10.00 (initial fee) = $20.50 (for 1 hour)

Now that you have the price for 1 hour including the initial fee, now you need to find the price for each hour after that. Here's how I did that:

I created a graph that looked like this:

Hours: 1 2 3
Ieda: 19.50 30.50 41.50
Thanh: 20.50 31.00 41.50

Here's how I figured out the price for each hour:

Ieda:

Hour 1 (including initial price):
$11.00 + $8.50 = $19.50
Hour 2 (excluding initial price): Only add the hourly price after Hour 1!
$19.50 + $11.00 = $30.50
Hour 3 (excluding initial price):
$30.50 + $11.00 = $41.50

Thanh:

Hour 1 (including initial price):
$10.50 + $10.00 = $20.50
Hour 2 (excluding initial price):
$20.50 + $10.50 = $31.00
Hour 3 (excluding initial price):
$31.00 + $10.50 = $41.50

So, looking at the graph, their prices are the same once each instruction reaches 3 hours. ($41.50)

I hope I was able to help you! :)

5 0

2 years ago

Read 2 more answers

Greetings. As a beginner, I'm struggling a bit to learn calculus. May I know what is the derivative of x to the power 4 step by

elena-14-01-66 [18.8K]

If you're just starting calculus, perhaps you're asking about using the definition of the derivative to differentiate $x^4$ .

We have

$\dfrac{d}{dx} x^4 = \displaystyle \lim_{h\to0} \frac{(x+h)^4 - x^4}h$

Expand the numerator using the binomial theorem, then simplify and compute the limit.

$\dfrac{d}{dx} x^4 = \displaystyle \lim_{h\to0} \frac{(x^4+4hx^3 + 6h^2x^2 + 4h^3x + h^4) - x^4}h \\\\ ~~~~~~~~ = \lim_{h\to0} \frac{4hx^3 + 6h^2x^2 + 4h^3x + h^4}h \\\\ ~~~~~~~~ = \lim_{h\to0} (4x^3 + 6hx^2 + 4h^2x + h^3) = \boxed{4x^3}$

In general, the derivative of a power function $f(x) = x^n$ is $\frac{df}{dx} = nx^{n-1}$ . (This is the aptly-named "power rule" for differentiation.)