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3 years ago

5x-3y when x = 7 and y = -8

Mathematics

2 answers:

Vika [28.1K]3 years ago

6 0

By replacing x=7 and y= -8 we obtain
5x-3y= 5x7-3x(-8)=35+24=59
The answer is 59

Lynna [10]3 years ago

5 0

You place the values of x and y in the equation:

5(7)-3(-8)

35+24 (negatives cancel out)

59 is the answer

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A devastating freeze in California’s Central Valley in January 2007 wiped out approximately 75% of the state’s citrus crop. It t

inna [77]

The relationship between the percentage of frozen citrus crop, and the cost of box of oranges is an illustration of a linear function.

The linear equation of the function is: $g(P) =22.9P +7$ , while its inverse is: $g^{-1}(c) = \frac{c - 7}{22.9}$ .
The domain is from 0% to 100%, while the range is from 7 to 29.9

Given that:

$c = g(P)$

Input and Output quantity

The input quantity is the percentage of frozen citrus crop, while the output quantity is the cost of box of oranges

Linear Function

The given parameters can be written as:

$(P_1,c_1) = (20\%, 11.58)$

$(P_2,c_2) = (80\%, 25.32)$

Calculate the slope (m)

$m = \frac{c_2 - c_1}{P_2 - P_1}$

So, we have:

$m = \frac{25.32 - 11.58}{80\% - 20\%}$

$m = \frac{13.74}{60\%}$

$m = 22.9$

The equation is then calculated using:

$c =m(P - p_1) + c_1$

So, we have:

$c =22.9(P - 20\%) + 11.58$

$c =22.9P - 4.58 + 11.58$

$c =22.9P +7$

So, the function is:

$g(P) =22.9P +7$

The domain and the range

The domain is the possible input value (i.e. possible values of P).

Because P is a percentage, its possible values are 0% to 100%.

Hence, the domain of the function is: $[0\%,100\%]$

The range is the possible output value (i.e. possible values of c).

When P = 0% and 100%

$c = 22.9 \times 0\% + 7 = 7$

$c = 22.9 \times 100\% + 7 = 29.9$

Hence, the range of the function is: $[7,29.9]$

The meaning of $g^{-1}(12)$

$g^{-1}(12)$ is an inverse equation, where 12 represents the cost of box of oranges.

So, $g^{-1}(12)$ represents the percentage of frozen citrus crop, when the cost is $12.

The inverse formula

We have:

$c =22.9P +7$

Make P the subject

$22.9P = c - 7$

Divide by 22.9

$P = \frac{c - 7}{22.9}$

So, the inverse function is:

$g^{-1}(c) = \frac{c - 7}{22.9}$

This is used to calculate the percentage of frozen citrus crop, when the cost is known.

$g^{-1}(c) = \frac{c - 7}{22.9}$

Substitute 12 for c

$g^{-1}(12) = \frac{12 - 7}{22.9}$

$g^{-1}(12) = \frac{5}{22.9}$

$g^{-1}(12) = 22\%$

Read more about linear equations at:

brainly.com/question/19770987

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3 years ago

You and your brother are reading the same novel. You want to get ahead of him in the book, so you decide to read 30minutes longe

lana66690 [7]

(Y) me 30 minutes longer (X) brother
brothers total minutes read are equal to my minutes read plus 30 more minutes
X= Y+30

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3 years ago

After 5 throws in a game of darts, Brent's mean score was 32. Calculate his total score.

ehidna [41]

1.To know this answer, we need to know some vocabulary that's used in t. Most people don't know how to solve questions if they have hard Vocabulary and what the question is Asking

Mean=The average of all his throws

It's asking us to calculate his total score

2. Find Clues to help you solve word problems

Finding clues in Word Problems is a very important part a lot of people skip but this helps you solve the question easier

5 throws and Mean Score is 32 are the clues

3. Guess and check

The method to this thingy is called guess and check. There is another method which is slightly harder and i just don't want to do it.

Let's just say his scores were... 5, 6, 4, 5,10Add them up and you get 30Then 30/5

Let's try bigger numbers

20+25+20+20

If you like this method, you may try it another method is called work Backwards

5x32=160

Then divide 160 by 5 to double check and you get 32!!

========================================

Therefore, the answer s 160 as his total score

hope this gives you a clue to what we are doing and when you have a question like this, I really hope you understand the concept

Hope this helped (:

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3 years ago

THIS IS THE LAST ONE NUMBER 9

Cloud [144]

Answer:(d)

Step-by-step explanation:

Given

AB=AC

$\therefore$ We can write

$\angle ABC=\angle ACB\ \quad \text{[angles corresponding to equal sides are equal]}$

$\angle ABC=\angle BCA=\angle ACB=65^{\circ}$

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3 years ago

Write 2/5 + 1/3 answer as a fraction. Show your work.

Diano4ka-milaya [45]

Answer: 11/15

Step-by-step explanation:2

2 × 3

5 × 3

1 × 5

3 × 5

6 + 5

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3 years ago