Question

3 pineapples, 2 cabbages and 6 bananas cost a total of $27.

Answer 1

3p + 2c + 6b = 27
2p + 3c + 4b = 23
4p + 1c + 8b = 31
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take any 2 equations and eliminate a variable

3p + 2c + 6b = 27
4p + 1c + 8b = 31....multiply by -2
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3p + 2c + 6b = 27
-8p - 2c - 16b = - 62 (result of multiplying by -2)
--------------------add
-5p - 10b = - 35

Now take one equation, and the other equation that u have not used already, and eliminate the same variable.

4p + 1c + 8b = 31.....multiply by -3
2p + 3c + 4b = 23
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-12p - 3c - 24b = - 93 (result of multiplying by -3)
2p + 3c + 4b = 23
----------------------add
-10p - 20b = - 70

now take ur 2 equations that u eliminated the c in, and eliminate another variable

-5p - 10b = -35......multiply by -2
-10p - 20b = -70
---------------------
10p + 20b = 70 (result of multiplying by -2)
-10p - 20b = -70
-------------------add
0 = 0

when u get a result such as  0 = 0....this means there is infinite solutions to this problem