69. (4x2 - 9x + 7) + (x2 + 5x - 1) – (5x2 - 4x + 5) = how much?
(Select two correct alternatives.)
(1) 1
(2) x2 + 3x - 2
(3) 2x2 - 2x + 5
(4) 2°
Answers
Answered by
1
Step-by-step explanation:
(4×2-9x+7)+(x^2+5x-1)-(5×2-4x+5)
=(8+7-9x)+(x^2+5x-1)-(10+5-4x)
=15-9x+x^2+5x-1-10-5+4x
=x^2-9x+5x+4x+15-1-10-5
=x^2-4x+14-10-5
=x^2-4x+4-5
=x^2-4x-1
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