Răspuns :
1.a+b+c=75+32=107
2a+b+c=75*2+32=150+32=182
3a+2b+2c=75*3+2*32=225+64=289
2.a+b+c=213+78=291
2a+2b+3c=2*213+3*78=426+234=680
ac+bc=a+b+2c=213+48*2=213+96=309
3.a+2b+c=a+b+b+c=24+5=29
2a+5b+3c=2*(a+b)+2*(b+c)+b=2*24+2*5+b=58+b=…de aici un mai stiu
2a+b+c=75*2+32=150+32=182
3a+2b+2c=75*3+2*32=225+64=289
2.a+b+c=213+78=291
2a+2b+3c=2*213+3*78=426+234=680
ac+bc=a+b+2c=213+48*2=213+96=309
3.a+2b+c=a+b+b+c=24+5=29
2a+5b+3c=2*(a+b)+2*(b+c)+b=2*24+2*5+b=58+b=…de aici un mai stiu