Question

Se stie ca x+y=1250. Calculati :
A)x+y+5
B)x+5+y
C)3+x+y
D)x-3+y
E)x+(y+10)
F)x+x+y+y

Answer 1

 daca   x + y = 1250 

A)x+y+5  = 1250 + 5 = 1255
B)x+5+y  = ( x +  y  ) + 5 = 1250 + 5 = 1255
C)3+x+y   = 3 + ( x +y) = 3 + 1250 = 1253
D)x-3+y    = ( x + y ) -3 = 1250 -3 = 1247
E)x+(y+10) = ( x +y)  + 10 = 1250 + 10 = 1260
F)x+x+y+y = 2x + 2y = 2 · ( x +y) = 2 · 1250 = 2500 

Answer 2

$x+y=1250 \\ a).x+y+5=1250+5=1255 \\ b).x+5+y=x+y+5=1250+5=1255 \\ c).3+x+y=3+1250=1253 \\ d).x-3+y=x+y-3=1250-3=1247 \\ e).x+(y+10)=x+y+10=1250+10=1260 \\ f).x+x+y+y=2x+2y=2(x+y)=2 \cdot 1250=2500$