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secondary 3 | E Maths
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i rly need help thanks so much in advanceee
x + y + z = 2019
A few possible ways.
1. z = 672, y = 673, x = 674
2. z = 671, y = 672, x = 676
3. z = 671, y = 673, x = 675
One of these should fit the second equation, but I am lazy to evaluate.
x + y + z = 2019
x = 2019 - y - z
Sub this into 2x + 3y + 4z = 6055,
2(2019 - y - z) + 3y + 4z = 6055
4038 - 2y - 2z + 3y + 4z = 6055
4038 + 2z + y = 6055
y = 6055 - 4038 - 2z
y = 2017 - 2z
Sub this into x = 2019 - y - z,
x = 2019 - (2017 - 2z) - z
x = z + 2
Since x > y > z > 670, and x = z + 2, and given they are all positive integers,
y = z + 1 so that it is in between z and x.
Then 2019 = z + 2 + z + 1 + z
2019 = 3z + 3
2016 = 3z
z = 2016 ÷ 3 = 672
y = 673 and z = 674
There is also no need to guess and check
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