10× (2y-10) =? (X+5) × (5×-1) =? (7-2x) × (2x-7) =?

1.) 20y-100 =0
20y = 100
y = 100/20
y = 5
2.) 5x² +25 -x -5 =
= 5x -x +20
3.) 14x - 4x² -49 + 14x
-4x² -49



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