Ask a few exercises about removing brackets and merging similar items in mathematics of grade one in junior high school~ Must copy the original title, talented prawns help me acridine 1: Remove the brackets and merge the similar items: （1）a+（-b+c-d）（2）a-(-b=c-d)（3）-(p+q)+（m-n） （4）（r+s）-（p-q）（5）3（2xy-y）-2xy（6）a+（5a-3b）-（a-2b） （7）x+[x+(-2x-4y)]（8）1/2（a+4b）-1/3（3a-6b）(9)a+(2a-3c) （10）6x+2（x+3）（11）3x-（4y-2x）+y（12）（2x-2y）-（2y-3x） （13）（x-y）-2（x-3x-2y） 2: According to the rule of removing brackets, the__ Fill in "+" or "-" （1）a __ （-b-c）=a-b+c （2）a __ （b-c-d）=a-b+c+d （3）__ （a-b）__ （c+d）=c+d-a+b 3: Mr. Zhang asked the students to calculate "the value of the algebraic formula A & sup2; + a (a + b) - 2A & sup2; - 2b when a = 0.25 and B = - 0.37." Xiao Ming said that the result can be obtained without any conditions. Do you think what he said is reasonable? Give the reasons 4: First simplify, then find the value of the algebraic formula: (3a-5b) - 2 (3a-b), where a = - 2, B = 3

Ask a few exercises about removing brackets and merging similar items in mathematics of grade one in junior high school~ Must copy the original title, talented prawns help me acridine 1: Remove the brackets and merge the similar items: （1）a+（-b+c-d）（2）a-(-b=c-d)（3）-(p+q)+（m-n） （4）（r+s）-（p-q）（5）3（2xy-y）-2xy（6）a+（5a-3b）-（a-2b） （7）x+[x+(-2x-4y)]（8）1/2（a+4b）-1/3（3a-6b）(9)a+(2a-3c) （10）6x+2（x+3）（11）3x-（4y-2x）+y（12）（2x-2y）-（2y-3x） （13）（x-y）-2（x-3x-2y） 2: According to the rule of removing brackets, the__ Fill in "+" or "-" （1）a __ （-b-c）=a-b+c （2）a __ （b-c-d）=a-b+c+d （3）__ （a-b）__ （c+d）=c+d-a+b 3: Mr. Zhang asked the students to calculate "the value of the algebraic formula A & sup2; + a (a + b) - 2A & sup2; - 2b when a = 0.25 and B = - 0.37." Xiao Ming said that the result can be obtained without any conditions. Do you think what he said is reasonable? Give the reasons 4: First simplify, then find the value of the algebraic formula: (3a-5b) - 2 (3a-b), where a = - 2, B = 3

1: Remove the brackets and merge the similar items:
（1）a+（-b+c-d）
Original formula = A-B + C-D
（2）a-(-b+c-d)
Original formula = a + B-C + D
(3）-(p+q)+（m-n）
The original formula = - P + Q + M-N
(4)（r+s）-（p-q）
The original formula = R + S-P + Q
（5）3（2xy-y）-2xy
Original formula = 6xy-3y-2xy
=4xy-3y
（6）a+（5a-3b）-（a-2b）
Original formula = a + 5a-3b-a + 2B
=5a-b
（7）x+[x+(-2x-4y)]
Original formula = x + x-2y-4y
=2x-6y
（8）1/2（a+4b）-1/3
Original formula = 1 / 2A + 2b-1 / 3
(9)a+(2a-3c)
The original formula is a + 2a-3c
=3a-3c
（10）6x+2（x+3）
Original formula = 6x + 2x + 3
=8x+3
（11）3x-（4y-2x）+y
Original formula = 3x-4y + 2x + y
=5x-3y
（12）（2x-2y）-（2y-3x）
Original formula = 2x-2y-2x + 3Y
=y
（13）（x-y）-2（x-3x-2y）
Original formula = x-y-2x + 6x + 4Y
=5x+3y
2: According to the rule of removing brackets, the__ Fill in "+" or "-"
（1）a _ Is the title wrong_ （-b-c）=a-b+c
（2）a _ -_ （b-c-d）=a-b+c+d
（3）_ -_ （a-b）_ +_ （c+d）=c+d-a+b
3: Mr. Zhang asked the students to calculate "the value of the algebraic formula A & sup2; + a (a + b) - 2A & sup2; - 2b when a = 0.25 and B = - 0.37." Xiao Ming said that the result can be obtained without any conditions. Do you think what he said is reasonable? Give the reasons
The original formula = A & sup2; + a (a + b) - 2A & sup2; - 2b
=a²+a²+ab-2a²-2b
=ab-2b
What Xiao Ming said is wrong, because we still need to replace the numbers. The reason is that this process should be simplified
4: First simplify, then find the value of the algebraic formula: (3a-5b) - 2 (3a-b), where a = - 2, B = 3
Original formula = 3a-5b-6a + 2B
=-3a-3b
When a = - 2, B = 3
（-3）*（-2）-3*3
=6-9
=-3