Besoin d'aide svp,je galère de trop :(... Maths niveau 4ème!
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A= 3x - 5 + 5(2x -2)
= 3x - 5 +10x - 10
= 3x +10x -5-10
= 13x -15
B= 4y - 6(3-2y) + 4(y-1)
= 4y - 18 -12y + 4y - 4
= 4y -12y + 4y -18-4
= -4y -22
C= 5t² + 3(2t-3) -2t(t-5)
= 5t² + 6t-9 - 2t² +10t
= 5t² - 2t² + 6t +10t -9
= 3t² +16t -9