If x + 4y = 18 and x - 4y = 2, then x = ?

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Me asap on # : explain how factoring a trinomial, ax^2+ bx+ c, when a does not equal 1 different from factoring a trinomial when a = 1.

The tile along the edge of a triangular community pool needs to be replaced? ?

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25