a)2c(5c-3)-(c-2)(c-4) a)(y-2)(y+3)-(y-1)²=3y-7
10c²-6-(c²-6c+8) 4(a+5)²-(4a²+40a)
10c²-6-c²+6c-8 4(a²10a+25)-(4a²+40a)
9c²-14+6c 4a²+40a+100-4a²-40a=100
b)(a-4)(a+6)+(a-10)(a-2)
a²+2a-24+a²-12a+20
2a²-10a-4
