Question

A rectangle has a perimeter of 12 x +8y. If one side of the rectangle is 4x-2y. write and expression of the other side.
2(2x +y) is this right

Answer 1

check
half perimeter = 6 x + 4 y
is that
4 x - 2 y + 4 x + 2 y
no
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now
6 x + 4 y = 4 x - 2y + a x + b y
6 x = 4 x + a x
a = 2
4 y = - 2 y + b y
b = 6
so I get 2 x + 6 y
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check mine
6 x + 4 y = 4 x - 2 y + 2 x + 6 y ?????
6 x + 4 y = 6 x + 4 y ..........sure enough