3(a-8)-(5-2a) dla a=-0,5 4(x-y)-(-x+y) dla x=½, y=¼

3(a-8)-(5-2a)=3a-24-5+2a=5a-19 5×(-0,5)-19=-2,5-19=-21,5 4(x-y)-(-x+y)=4x-4y+x-y=5x-5y ½=0,5 ¼=0,25 5×0,5-5×0,25=2,5-1,25=1,25

3(0,5-8) - (5-2 * 0,5) = 3*(-7,5)-5+1 = -22,5 - 6 = -28, 5 4* (1/2-1/4)-(-1/2+1/4) = 4* (2/4-1/4)-1/2-1/4 = 4* 1/4-2/4-1/4= 1-2/4-1/4 = 1/4 nie jestem pewna