Question

Dacax+y=8 si y+2z=35 ,calculati :a;5x+13y+16z b;3y-2x+10z c;7x+10y+6z d;4(2z+y)+3x+3y

Answer 1

Răspuns:

Explicație pas cu pas:

x+y=8 ;

y+2z=35

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a) 5x+13y+16z = 5x+5y+8y+16z =

= 5(x+y) + 8(y+2z) = 5·8+8·35 = 8(5+35) = 8·40 = 320

b) 3y-2x+10z = -2x-2y+5y+10z = (-2)·(x+y) +5(y+2z) =

= -2·8 + 5·35 = -16+175 = 159

c) 7x+10y+6z = 7x+7y+3y+6z =

= 7(x+y) + 3(y+z) = 7·8 + 3·35 = 56+105 = 161

d) 4(2z+y)+3x+3y = 4(y+2z) + 3(x+y) =

= 4·35 +3·8 = 140 +24 = 164