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Equation Exercise (Posted on 2014-12-16)

a,b,c,d and e satisfy this system of equations:

2a+b+c+d+e = 6
a+2b+c+d+e = 12
a+b+2c+d+e = 24
a+b+c+2d+e = 48
a+b+c+d+2e = 96

Find 3d+2e without solving the above system.

See The Solution Submitted by K Sengupta

Rating: 5.0000 (1 votes)

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Another solution

Comment 3 of 3 |

Label the equations A, B, C, D, E in order.

Then the linear combination -5A-5B-5C+13D+7E evaluates to 18d+12e = 1086.

Then 3d+2e = 1086/6 = 181.

Posted by Brian Smith on 2016-11-24 16:02:23

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