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satela [25.4K]
3 years ago
11

Solve using elimination. 3x − 5y = 18 -10x + 5y = 10

Mathematics
2 answers:
olga55 [171]3 years ago
5 0

3x - 5y = 18 over

-10x + 5y = 10

Add them because the 5y's have the right symbols for us to add

-7x = 28

Divide

x = -4

Now you can plug in -4 for x in one equation, I would use the first equation!

3(-4) - 5y = 18

-12 - 5y = 18

Add 12

-5y = 30

Divide

y = -6

Your solutions are going to be:

x = -4

y = -6

To check your work plug x and y into one equation:

3(-4) - 5(-6) = 18

-12 + 30 = 18

18 = 18

Since 18 does equal 18 you know that your solution's work!

GalinKa [24]3 years ago
4 0
Yes that is the right answer
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Question isn't well formatted :

If I have 48 cards and and gave 10 to my friend and I have 38 left. what fraction of original number of card do I have left.

Answer:

0.7917

Step-by-step explanation:

If I have 48 cards and and gave 10 to my friend and I have 38 left what what fractionbb be is my original number of cards

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4 0
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