X= 1 1/7 to solve this equation.

A: When x= 1 1/7, the algebraic expressions 4x-5 and 3x-6 have opposite values.

2. Suppose there are X groups, according to the meaning of the question 8x= 12(x-2).

Solving this equation gives x=6.

So there are 6×8=48 students.

There are 48 students.

3. Let the original price be X yuan, depending on the meaning of the question.

x( 1- 15%)= 56. 1

To solve this equation, x=66.

A: Set the original price as 66 yuan.

Let the number in the tenth place of this three-digit number be X.

[ 100(x+ 1)+ 10x+3x-2]+[ 100(3x-2)+ 10x+x+ 1]= 1 17 1

To solve this equation, x=3.

So100 (x+1)+10x+3x-2 =100 (3+1)+10× 3+3× 3-2 =

A: This three-digit number is 437.

5, set up three classes * * * to donate X copies, according to the meaning of the question.

152+x/3+40%x=x

To solve this equation, x=570.

A: Three classes donated 570 copies.

6. Solve Equation 2(2x-2)= 1-2x.

X=5/6，

Replace 8-K=2(x+ 1) with x=5/6.

Get 8-K=2(5/6+ 1), get K= 13/3.

So when K= 13/3, the solutions of equation 2(2x-2)= 1-2x and 8-K=2(x+ 1) are the same.

Solution: Suppose two kinds of trees * * * planted X trees.

(x/2+56)+(x/3- 14)=x

Solve this equation X=252.

252÷2+56= 182,252÷3- 14=70

A: Poplar 182, fir 70.