1.(3xpangkat2+-1)+(x pamgkat 2-5x+6) 2.2(x+2y-xy)+5(2x-3y+5xy0

1. (3x²-1) + (x²-5x+6) = 3x²+x²-5x-1+6
                                  = 4x²-5x+5
2. 2(x+2y-xy) + 5(2x-3y+5xy) = (2x+4y-2xy) + (10x-15y+25xy)
                                               = 2x+10x+4y-15y-2xy+25xy
                                               = 12x-11y+23xy