Răspuns:
1.600,1000,1391,650
Explicație pas cu pas:
2)73(73+1)/2=2701, 52(52+1)/2=1378,66(66+1)/2=2211,93(93+1)2=4371
3)a)5(3x+1)+15=50 x=6
B)4x+64=68 x=1
C)3x+4x+4+8=33,x=3
D)18x+7x -14-21x=2,x=4
E)3+2x-2=17, x=6