7th grade math ternary equation page 114 exercise 8 4 answers

It's not a human-taught version?

2012-12-01 16:48286440282|Level 2, set up x cubic meters to make the desktop, then use (12-x) square meters to make the table legs, 4 20x = 400 (12-x), x = 10, 12-x = 2, 3, set x days to manufacture a part, then (30-x) days to make B parts, 500x = 250 (30-x), x = 10, 30-x = 20, 4, set a total of x hours, 1, 2 15 + x 5 = 1, 2 + 3x = 15

x = 13 3 hours, 5, set by x people for 2 hours, 2x 80 + 8 (x + 5) 80 = 3 4,

3 Solution: Set up clothes... for x.

x+10)\12=(x+2)\7

Count yourself...

x=A:.

5 Solution: There are x in a box. According to the title, yes.

8x+4)\5-(11x+1)\7=1

7(8x+4)-5(11x+1)=35

56x+28-55x-5=35

x=126 Set a slope x m flat road y midan brother.

3/3 x + 4/4 y 54/60

5/5 x + 4/4 y 42/60 (sorry for the answer to be late or calculated) 8 Set the discount before a product X yuan, a B product Y original.

60x+30y＝1080 （1）

50x+10y－840 （2）

1 deformation 2x+y 36 (3).

2 deformations 5x+y 84 (4).

4)-(3) Brigade 3x 48

x＝16

3 (1) Solution: Substituting x=2y into the equation 2x-z=7 gives 4y-z=7

Multiply the equation y-3z=10 by 4 and subtract 4y-z=7, -11z=33, z=-3

Then substituting z=-3 into the equation y-3z=10 uses y=1

again x=2y, so x=2

So the solution of this ternary system of equations is x=2, y=1, z=-3

2) Solution: y=4+2z is obtained by the equation y-2z=4

Substituting y=4+2z into the equation yields {2x+4z=-3(1),3x+2z=5(2)}

Multiply Eq. (2) by 2 and subtract Eq. (1) to get 4x=13, x=13 4

Substituting x=13 4 into 3x+y=9 gives y=-3 4, z=-19 8

So the solution of this ternary system of equations is x=13 4,y=-3 4,z=-19 8

4 solution: substituting 3x-5y=8 into 3x-5y+2z=4 to get 2z=-4, z=-2

Substituting z=-2 into the equation 2x+3y-z=1 gives 2x+3y=-1

Multiply equation 3x-5y=8 by 2 and subtract equation 2x+3y=-1 by 3 to get -19y=19,y=

So the solution of this ternary system of equations is x=1, y=-1, z=-2

5 Solution: Let A be x, B be y, and C be z, and the system of equations x+y+z=26, x-y=1, 2x+z-y=18 can be obtained according to the problem

x=y+1 is obtained from x-y=1

Substituting x=y+1 into the system of equations x+y+z=26, 2x+z-y=18, we get {2y+z=25(1)y+z=16(2)},1)-(2) gives y=9

So x=10, z=7, so the three numbers A, B, and C are 10, 9, and 7 respectively

Solution 6: obtained by x+y=16, x=16-y

Substituting x=16-y into z+x=10 gives z-y=-6

Add z-y=-6 and y+z=12 to give 2z=6, z=3, y=9, x=7

Therefore, the solution of this ternary system of equations is x=7,y=9,z=3,

There are books, but you can't tell you the phrase "Unary Equation (2) Exercise Problem 3 and 101 Pages of Practice Questions". Please specify the number of pages.

If it is a third question on page 111 of A, it does this.

2x-1 Multiply both sides by 21 to get (2x-1

That is, 30 (2x-1) = 70x-3

Remove the parentheses to get 60x-30=70x-3

Shift, we get -10x=27

Divide both sides by -10 to get x=

。。。Isn't this a dollar once in a while, there's something hard to solve.

3、（1）c=1

a+b+c=0

a-b+c=3

2)a=1/2 b=-3/2 c=1

4. Add a+b-c=0 and 3a-b+c=2 to obtain: 4a=2, i.e., a=1 2

Add a+b-c=0 and 2a+b+c=1 to obtain: 3a+2b=1, and bring a=1 and close 2 into b=-1 4

Bringing a=1 2 and b=-1 4 into a+b-c=0 gives c=1 4

So a=1 2 b=-1 4 c=1 4

5. (1) Multiply the formula x 2-y 3-z 3=4 3 by 6 to get 3x-2y-2z=8, and add 3x-2y-2z=8 and 2x-y+2z=-25 to get 5x-3y=-17

Multiply x+2y-z=30 by 2 and add 2x-y+2z=-25 to get 4x+3y=35

Added from 5x-3y=-17 and 4x+3y=35, 9x=18 i.e. x=2, then y=9 can be solved

Bringing x=2 and y=9 into x+2y-z=30 results in z=-10

So x=2, y=9, z=-10

2) From y:x=3:2, we get x=2 3y

From y:z=5:4 we get z=4 5y

Bringing x=2 3y and z=4 5y into x+y+z=111 gives 2 3y+y+4 5y=111

Then 37 15 y=111, i.e. y=45

Because x=2 3y, x=30, and because the neutral basis is z=4 5y, z=36

6. It can be obtained from the question.

a-b+c=-9

4a-2b+c= -20

a+b+c=-4

Add a-b+c=-9 and a+b+c=-4 to get 2a+2c=-13

Multiplying a+b+c=-4 by 2 and 4a-2b+c= -20 gives 6a+3c=-28, which is obtained by 2a+2c=-13 and 6a+3c=-28, a=-17 6, c=-11 3

Bring a=-17 6,c=-11 3 into a+b+c=-4 to get b=5 2

So a=-17 6, b=5 2, c=-11 3

Split vertical x=nine elimination source disadvantage points to twenty-nine x=5

y=18/13 Na 19 y=0

z=eighteen to nineteen z=-3

X A-shaped steel plates and Y B-shaped steel plates are used.

2x+y=15

x+2y=18

Solution. x=4y=7

Lazy students. We are not your teachers, and we don't have the teaching materials you say!

X A steel plate and Y B steel plate are used for dissolution.

2x+y=15

x+2y=18

The solution is x=4y=7

Hee-hee......

X fast A-shaped steel plate for dissolution, Y B-shaped steel plate.

2x+y=15

x+2y=18

x=4y=7

Answer:..

X A-shaped steel plates and Y B-shaped steel plates are used.

2x+y=15

x+2y=18

Solution. x=4

y=7 A: 4 A-shaped steel plates and 7 B-shaped steel plates are used.