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2 years ago

9x - 3y = -42 and -9x + 8y =22

Mathematics

1 answer:

ASHA 777 [7]2 years ago

8 0

Answer:

(-5 1/9, -4)

Step-by-step explanation:

Add the equations

5y=-20

y=-4

-9x+8(-4)=22

-9x-32=22

-9x=46

x= - 5 1/9

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A coffee bean processor can dry 4,815 pounds of coffee beans in 3 hours which unit rate correctly reflects the speed of the proc

zimovet [89]

Answer:

605 pounds/hour

Step-by-step explanation:

Given that a coffee bean processor can dry 4815 pounds of coffee in 3 hours.

We have to find the speed of the processor

By speed of the processor here we mean the unit rate i.e. no of pounds of coffee beans that the processor can process in one hour.

This is a question of direct variation

Since we have for 3 hours 4815

for 1 hour = $\frac{4815}{3} =605$ pounds/hour

So answer is 605 pounds/hour

Verify:

If unit rate is 605 pounds/hour, for 3 hours =605(3) = 4815 pounds

Thus verified

7 0

2 years ago

Read 2 more answers

Natalia solved the problem 74.4/12=6.2. complete the model with partial products check Natalia's work using multiplication

tia_tia [17]

Answer:

Natalia's work is wrong.

Step-by-step explanation:

Natalia divided a decimal number by an entire number. Since division is a operation derived from multiplication, the best approach to check if work was good is multiplying the given result by denomination, that is:

1) $x = 6.2\times 12$ Given.

2) $x = \left(6+0.2\right)\times 12$ Definition of addition.

3) $x = 6\times 12 + 0.2\times 12$ Distributive property.

4) $x = 72 + \frac{2}{10}\times 12$ Definitions of multiplication and decimal number.

5) $x = 72 +[2\cdot (10)^{-1}]\cdot 12$ Definition of division/Associative property.

6) $x = 72 + [2\cdot 12]\cdot (10)^{-1}$ Associative property.

7) $x = 72 + 24\cdot 10^{-1}$ Definition of multiplication.

8) $x = 72 + \frac{24}{10}$ Definition of divsion.

9) $x = 72 + 2.4$ Defintion of decimal number.

10) $x = 74.4$ Definition of addition/Result

Natalia's work is wrong.

5 0

2 years ago

The ratio of the perimeter of square RSTU to the perimeter of square WXYZ is 1 to 3. The area of square RSTU is 36 square inches

Ainat [17]

√36 square inches = 6 inches (length of sq RSTU)
6 inches x 4=24 inches (per. of sq RSTU)
-----------------------------------
1u=24 inches
3u=24 inches x 3=72 inches (per. of sq WXYZ)
-----------------------------------
72 inches ÷ 4=18 inches (length of sq WXYZ)
18 inches x 18 inches = 324 square inches( area of sq WXYZ)

Ans: 324 square inches

5 0

2 years ago

Read 2 more answers

Ian has 12.2 ounce bottle of ketchip. He uses 1/20 of the ketchup every time he has a buffalo burger How many ounces of ketchup

tatiyna

If Ian uses 1/20 of the ketchup 4 times, this is equal to 4/20, or $\frac{4}{20}$ .

$\frac{4}{20}$ can be simplified to $\frac{1}{5}$ , which means we need to work out $\frac{1}{5}$ of 12.2

$\frac{1}{5}$ is equivalent to 20%, which as a decimal is 0.2

0.2 x 12.2 = 2.44 - however, this is how much he has used, and we need to figure out how much is left.

12.2 - 2.44 = 9.76

So, Ian has 9.76 oz remaining :)

4 0

2 years ago

Using Normal Distribution to Analyze Data Martin suspects that people carry less cash with them than they used to because of cre

jek_recluse [69]

Answer:

Step-by-step explanation:

Sample size = 95

X=cash carried by the persons

x bar = 8.00

s = sample std dev = 2.50

Std error = $\frac{s}{\sqrt{n} } =\frac{2.5}{\sqrt{95} } \\=0.2565$