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4 years ago

How do you solve system of eqautions using substitution

1 answer:

8 0

Well basically you are plugging in variables. Lets use a random but simple system of equations.
y = 2x - 3
6x + 8y = 20
Now you need to plug in the top equation, which equals y, into the bottom equation.
6x + 8(2x - 3) = 20
6x + 16x - 24 = 20
Combine like terms.
22x - 24 = 20
Add 24 to both sides.
22x = 44
Divide.
x = 2
Now plug in 2 in any of the original equations.
y = 2x - 3
y = 2(2) - 3
y = 4 - 3
y = 1
So your solution is (2,1). And thats how you use substitution.
I hope this helps love! :)

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lydia buys 5 pounds of apples and 3 pounds of bananas for a total of $8.50. ari buys 3 pounds of apples and 2 pounds of bananas

gavmur [86]

Answer: The price per pound of apples is $ 1.25 and the price per pound of bananas is $ 0.75.

Step-by-step explanation: Given that lydia buys 5 pounds of apples and 3 pounds of bananas for a total of $8.50 whereas Ari buys 3 pounds of apples and 2 pounds of bananas for a total of $5.25.

We are to find the price per pound of apples and bananas.

The cost per pound of apples is represented by x dollars and the cost per pound of bananas is represented by y dollars.

Then, according to the given information, the system of equations describing the situation is as follows:

$5x+3y=8.50~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~(i)\\\\3x+2y=5.25~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~(ii)$

Multiplying equation (i) by 2, we have

$2(5x+3y)=2\times 8.50\\\\\Rightarrow 10x+6y=17~~~~~~~~~~~~~~~~~~~~~~~~(iii)$

and multiplying equation (ii) by 3, we have

$3(3x+2y)=3\times 5.25\\\\\Rightarrow 9x+6y=15.75~~~~~~~~~~~~~~~~~~~~~~~~(iv)$

To eliminate y, we subtract equation (iv) from equation (iii) and we arrive at

$(10x+6y)-(9x+6y)=17-15.75\\\\\Rightarrow x=1.25.$

From equation (i), we get

$5\times 1.25+3y=8.50\\\\\Rightarrow 6.25+3y=8.50\\\\\Rightarrow 3y=2.25\\\\\Rightarrow y=0.75.$

Thus, the price per pound of apples is $ 1.25 and the price per pound of bananas is $ 0.75.

7 0

4 years ago

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Idk this bs its stupid.?!

LekaFEV [45]

Answer:y=-3/2x-1

Step-by-step explanation:-3/2 is your slope which is your m and -1 is your b x is left alone.

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Which sampling method divides the population up into sections, randomly selects some of those sections, then chooses all the m

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Which sampling method divides the population up into sections, randomly selects some of those sections, then chooses all the members from the selected sections to study?

Answer: The above mentioned type of sampling is called cluster sampling.

Cluster sampling is a sampling technique in which the entire population of interest is divided into clusters or groups, then the investigator randomly selects some of these clusters and all the members of these randomly selected clusters are investigated.

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3 years ago

Use a translation rule to describe the translation of ABC that is 6 units to the right and 10 units down.

vesna_86 [32]

Answer:

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Step-by-step explanation:

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(x, y ) → (x + 6, y - 10 )

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