How to solve the equation of addition and subtraction explain the method, you can also give an exam

If all the unknowns are placed on the left, what constant is added on the left, what is subtracted on both sides of the equation, what is subtracted on the left, what is added on both sides, multiplication and division is also a truth, until there is no addition or subtraction, the most earthy way!

Like. ax+b=c

If you have +b on the left, you will subtract b on both sides

ax+b-b=c-b

i.e. ax=c-b

If there is a multiplication of a on the left, both sides will be divided by a

ax/a=(c-b)/a

i.e. x=(c-b) a

That's it, so it's done, and it's reasonable to push it!

For example, 10x+4=5

The two sides of the equal sign are subtracted by 4

Eliminate real numbers on the side of the unknown x.

Then 10x+4-4=5-4

So 10x=1 is the same. Find x

then the elimination factor is 10

Divide by 10 on both sides of the equal sign

x=1/10

If you don't multiply and divide.

x+4=5 can be subtracted by 4 directly on both sides. x=1

Problem 1: How to solve the subtraction equation For example, the middle state.

Solution: -12+12=26+12

38 There is one more.

Solution: 12- +6+

Question 2: How to solve an equation by addition and subtraction of fractions The equation file or the simplest common denominator (least common multiple) multiplied on both sides

Calculation of integral equations.

If there is an unknown number in the denominator, the result should be checked.

Problem 3: How to solve the equation where x minus 1 3 equals 2 5 x-1 3=2 5x=2 5+1 3

Problem 4: Solve the equation by addition and subtraction Solution: - get: 14x-14y=-68, that is, x-y=-2, x=y-2, substitute into get: 80(y-2)+49y=98, solve y=2, substitute y=2 into get: x=2-2=0

Then the solution of the system of equations is.

x=0 y=2

Question 5: How to solve equations with fractions in grade 5? For example: 2 1 + x = 6 5 Subtraction has to treat fractions as an integer:

2/1+x=6/5

x = 6/5 - 2/1 (2/2)

x base six-fifths - 2 (two equals ten fifths).

x = 6/5 - 10/5.

x = minus four fifths.

The purpose of using "addition and subtraction" to solve equations is to eliminate an unknown, so before using "addition and subtraction", it is necessary to make the coefficients of the same unknown in two equations in a binary or ternary cubic group the same or inverse of each other.

For example: 3x-2y=7 (1).

5x+2y=1 （2）

The unknowns in Eq. (1) and the y in Eq. (2) are inverses of each other. We can use the addition in "addition and subtraction" to eliminate the unknowns, and the y method is:

Add the terms on both sides of the two equations, 3 +5 = 8x, -2y + 2y = 0, 7 + 1 = 8) to obtain:

Then solve this unary equation.

Divide the two sides by the unknown coefficient 8 to get :

x=1。If the system of equations is like this.

3ⅹ+6y=10 （1）

6x+3y=8 （2）

You can start by using (1)x2 to get:

6x+12y=20 （3）

In this way, (1) becomes (3), and (3) is the same as the x coefficient in (2), and the subtraction method of "addition and subtraction" can be used, and (2) is subtracted from (3) to obtain:

9y = 12y = 1 again (1 3).

The steps to solve an equation by addition and subtraction are grouped below

1.First, move all terms containing unknowns to the left of the equation, and all constant terms to the right of squares.

2.The left and right sides of the equation merge similar terms (i.e., add or subtract).

3.Finally, both sides of the equation are divided by the coefficients of the unknowns.

5.The offer with a common divisor is reduced to the simplest, i.e., the equation is solved.

For example, -12=26

Solution: -12+12=26+12

There is another kind. Solution: 12- +6+

This ......How to solve the subtraction equation? I'm also new to ......

5a+3b=20………1）

30%a+20%b=5*26%……2) (2) 10, de:

3a+2b=13………3）

1) 3. Got:

15a+9b=60………4）

3) 5, got:

15a+10b=65………5）

5)-(4), get:

b = 5 substituted into (1), get:

5a+3×5=20

5a=5a=1 is solved as:

a=1b=5

5x+y=7 (1)

3x-y=1 (2)

Solution: (1) + (2) get:

8x=8x=1

Substituting x=1 into (1) gives :

5+y=7y=2

So: x=1

y=2Happy learning!

One plus two, 8x=8

x=1 is taking x=1 into any equation to find y

Solution: From , obtain: 8u+9v=6

From , get: 24u+25v=14

3-, gets: 2v=4

Divide both sides of the equation by 2 to get: v=2

u = -3/2