Răspuns:
Explicație pas cu pas:
c)
4x^2 - 9 - 4x^2 - 4x = 2x + 6 + 3
9 - 4x = 2x + 9
4x + 2x = 9 - 9
2x = 0
x = 0
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d)
2x^2 - 12x + 2x - x^2 - 6 + 3x = x^2 - 25 - 5x + 5
x^2 - 7x - 6 = x^2 - 5x - 20
7x - 5x = 20 - 6
2x = 14
x = 7
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e)
9x^2 - 25 - 8x^2 + 16x = x^2 - 3x + x - 3 - 40
x^2 + 16x - 25 = x^2 - 2x - 43
16x + 2x = 25 - 43
18x = -18
x = -1
