Question

a) Daca se stie a+3b = 5 si c = 8, calculeaza 4a+12b+5c
b) Daca se stie 2a+3b = 5 si 2c+b + 7, calculeaza 4a+7b+2c
c) Daca se stie x+2y = 5 si a+3b = 6, calculeaza 2x+4y+4a+12b si 8x+16y+8a+24b
d) Daca se stie 3x+y = 10si 2y+z = 3, calculeaza 9x+5y+z si 3x+5y+2z

Answer 1

ex.pct.a).       a+a+a+a+3b+3b+3b+3b+5c=4*(a+3b)+5*8=4*5+5*8=20+4=60
ex.pct.b)        2a+2a+3b+3b+b+2c=2*(2a+3b)+(2c+b)=2*5+7=10+7=17
ex.pct.c)       8*(x+2y)+8*(a+3b)=8*5+8*6=40+48=88
ex.pct.d)       3x+3x+3x+y+y+y+y+y+z=3*(3x+y)+(2y+z)=3*10+3=33
                    (3x+y)+2(2y+z)=10+2*3=1+6=16

Answer 2

A] 4a+12b=5x4                  B]5x2+7=
                                          10+7=17
4a+12b=20
5c:c=5
8x5=40
20+40=60                                 C]5x2+4x6=34       8x5+8x6=88
D]3x10+3=33
  10+3x2=16