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3 years ago

Use a system of linear equations with two variables and two equations to solve. A number is 9 more than another number. Twice

Mathematics

1 answer:

Troyanec [42]3 years ago

4 0

9514 1404 393

Answer:

(x, y) = (3, 12)

Step-by-step explanation:

Using the given variable definitions, we can write the equations ...

y = x + 9

2(x +y) = 30

Solving the second equation for y, we have ...

y = 15 -x

Substituting this into the first equation gives ...

15 -x = x +9

6 = 2x . . . . . . . . . add x-9

3 = x . . . . . . . . . . divide by 2

y = 3+9 = 12 . . . . substitute into the first equation

The numbers are (x, y) = (3, 12).

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Answer:ur answer is 96

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4 years ago

What is <br> 2x+y=-4<br> step by step please and i will give you 44 points for this!!!

Anni [7]

Answer: 0=0

Step-by-step explanation:

First you want to solve for x

2x+y=−4

Step 1: Add -y to both sides.

2x + y + −y =−4+ −y

2x=−y−4

Step 2: Divide both sides by 2.

2x/2= -y-4/2

x=-1/2y-2

Then you want to plug in your answer for x into the equation so:

2(-1/2y-2)+y=-4

Step 1: Simplify both sides of the equation.

2(-1/2y-2)+y=-4

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−y+−4+y=−4

(−y+y)+(−4)=−4(Combine Like Terms)

−4=−4

Step 2: Add 4 to both sides.

−4+4=−4+4

0=0.

Sorry if this wasn't the answer your looking for. If you need more help I suggest using Ma.th.Pa.pa calculator but with out the periods. Hope you have a good day :)

5 0

3 years ago

Juan ordered 20 pizzas for a party. 45% of the pizzas have 8 slices each. The remaining 55% of the pizzas have 12 slices each. C

Mama L [17]

Total number of pizzas Juan ordered $20$

Since, $45\%$ of pizzas have $8$ slices.

Therefore, number of pizzas with $8$ slices are: $45\%\times(20)$

$=\frac{45}{100} \times(20)$

$=\frac{45}{10} \times(2)$

$=\frac{90}{10}$

$=9$ pizzas

Also, since, $55\%$ of pizzas have $12$ slices.

Therefore, number of pizzas with $12$ slices are: $55\%\times(20)$

$=\frac{55}{100} \times(20)$

$=\frac{55}{10} \times(2)$

$=\frac{110}{10}$

$=11$ pizzas

Now, there are $9$ pizzas with $8$ slices and $11$ pizzas with $12$ slices.

Therefore, total number of slices of pizza are: $=(9)(8)+(11)(12)$

$=72+132$

$=204$ slices

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3 years ago

I am confused please can you help me

lorasvet [3.4K]

Domain x|x = -2, 2
range x|x = -1, 4

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3 years ago

Which is the least common denominator of 5/6 3/8

Tems11 [23]

To find the least common denominator, or lcd, you have to find the least common multiple, or lcm. To do that you find the multiples of each number until they equal each other. I set up a chart like this,

6 -

8 -

and then I start listing multiples so,

6 - 6, 12, 18, 24,

8 - 8, 16, 24,

I stop after I find a number they are both equal to. So to get to that number I would multiply 8 by 3, and 6 by 4. This gives me 24 as the lcd. If you need the lcd to add the fractions together, then whatever you did to the bottom do to the top. So 5/6 would become 20/24 and 3/8 would become 9/24.

Answer: 24

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3 years ago