solve :x+y+z =12<br /> 5x+10y+20z=105<br /> 10x+5y+20z=125<br />please give me a answer fast
Answers
Answer:
x = 7 , y = 3 , z = 2
Step-by-step explanation:
x + y + z = 12 ......(1)
5 x + 10y +20z = 105 ....(2)
10x + 5y +20z = 125 ........(3)
(1) x 20 ⇒ 20 x + 20y +20 z = 240
(2) x- 1 ⇒ -5x -10y - 20z = - 105
...................................................
15x + 10y = 135 .......(4)
solving (2) and (3)
5x - 5y = 20 .........(5)
(4) x 1 ⇒ 15x +10y = 135
(5) x2 ⇒ 10x - 10y = 40
.................................
25x = 175
x = 175 /25
= 7
sub x= 7 in equ (5)
5x -5y = 20
5(7) -5y = 20
-5y = 20 - 35
y = - 15 / -5
= 3
sub x= 7 , y = 3 in equ (1)
x + y + z = 12
7 + 3 + z = 12
z = 12 - 10
= 2