Question

x + y = 8 si y + 2z = 8 , calculati :
a) 5x + 13 y + 16 z = ?
b) 3y - 2x + 10 z =?
c) 7x + 10y + 6z =?
d) 4 ,,ori" ( 2z+y ) + 3x +3y =?


Va rog frumos a fie cat mai bine , dau 17 puncte :) va rog ajutati-ma !

Answer 1

  x+ y = 8
 y + 2z = 8

a) 5x + 13 y +16 z = 5x+5y+ 8y+16z=5*(x+y)+8(y+2z)=5*8+8*8=40+64=104

b) 3y - 2x + 10 z = -2x+3y+10z=-2x-2y +5y+10z= -2*(x+y)+5*(y+2z)=
= -2*8+5*8= -16+40= 24

c) 7x + 10y + 6z =7x+7y+3y+6z= 7*(x+y)+3*(y+2z)=7*8+3*8=56+24=80

d) 4 * ( 2z+y ) + 3x +3y =4*(y+2z)+3*(x+y)=4*8+3*8=32+24=56