Question

afla valoarea expresiei E=100×a-10×b stiind ca a×42+720-720:9=1060 Și 100-b:16+350:7=144

Answer 1

a×42+720- 720 : 9 = 1060
a×42+720- 80 = 1060
a×42+720 = 1060+80
a×42+720 = 1140
a×42= 1140-720
a×42=420
a=420:42
a=10

100 -b : 16 +350 : 7 = 144
100 -b : 16 +50= 144
100 -b : 16= 144 -50
100 -b : 16=94
b : 16=100-94
b:16=6
b=6×16
b=96

E =100 ×a - 10 ×b
E =100 ×10 - 10 ×96
E=1000-960
E=40

Answer 2

a x 42 +720 - 80 =1060
ax 42 +720 = 1060+ 80
ax 42 +720 = 1140
ax42 = 1140-720
ax42=420
a= 420:42
a=10

100 - b : 16 + 50 = 144
100 - b:16 = 144-50
100 -b : 16= 94
b:16= 100-94
b:16= 6
b= 6x16
b=96
E = 100 x 10 - 10 x 96
E= 1000-960
E = 40