2. solution: let a be x, b be y and c be z, and according to the meaning of the question, we can get the ternary linear equations:
x+y+z=35 ①
2x=y+5 ②
( 1/3)y=( 1/2)z ③
To solve this system of equations, we must:
x= 10
y= 15
z= 10
A: These three numbers are 10, 15 and 10.
Exercise 8.4
1 、( 1)x = 2y =-3z = 1/2(2)x =-(3/4)y = 5/3z = 2
2 、( 1)x = 5y =-2z = 1/3(2)x =- 1y = 1/2z = 3
Let the three-digit number be x, the tenth digit number be y and the hundredth digit number be z.
Meaning, meaning: x+z=y
7z=x+y+2
x+y+z= 14
To solve this system of equations, x=5.
y=7
z=2
A: This three-digit number is 275.
4、x=30
y=20
z= 16
5. Solution: According to the meaning of the question, we can list the ternary linear equations:
-2=a+b+c
20=a-b+c
(9/4)a+(3/2)b+ c =( 1/9)a+( 1/3)b+ c
To understand this system of equations, we get: a=6.
b=- 1 1
c=3