中1 maths問題!高手入!!超急!!

1. 10-2x+5-3x
=15-5x
2. 20-3x-30-y+4y
=-10-3x+3y
3. 負3x+4y+5x-2y
=2x+2y
4. 2x^2-2x-x^2+5x
=x^2+3x
5. 5-x-x^2+2-3x
=-x^2-4x+7
6. 2x+3x-4x
=x
7. 5(2x)(3x)(2y)
=60x^2 y
8. 5x(3x)+5x+3x
=15x^2+8x
1. multiply the difference of a and b by 7.
7(a-b)
2. subtract 4d from 5 times c.
5c-4d
3. add g to the product of e and f.and then multiply the sum by 8.
8(ef+g)
4. subtract 7 from 3 times h, and then divide the difference by 4 times i^2.
(3h-7)/4i^2
5. x+2x+4x
7x
6. 9-3p+7p-4
4p+5
7. 4x-2y-6x+9y
-2x+7y
8. 21y-40x+12x-9y
12y-28x
9.lucy buys r concert tickets for $1000.Express the average price of each ticket in terms of r.
1000/r
10.if a box can hold 4a oranges,express the number of oranges held by 15 boxes in terms of a.
60a
11.if the largest number among three consecutive number is x,express the sum of the three numbers in terms of x.
3x-3
之後就用列式作答
1. the calculations of the score for a general knowledge quiz is as follows:
each team has a base of 200 points.for the first round, 10 point will be given for each corract answer,and no point will be deducted for any incorrect answer or question given up.For the second round,20 point will be given for each correct answer, and 10 point will be deducted for each incorrect answer or question given up.

(a) team A answered x questions correctly in the first round. Find the score of team A after the first round.
200+10x-0
=200+10x
(b) in the second round, team A answered correctly, z questions wrongly and gave up 4 questions. Find the score of team A after these two round.
Is the question"team A answered y question correctly"?
If yes,the answer is:
200+10x+20y-10(z+4)
=200+10x+20y-10z-40
=160+10x+20y-10z

1. 10-2x+5-3x
=15-5x
2. 20-3x-30-y+4y
=-10-3x+3y
3. 負3x+4y+5x-2y
=2x+2y
4. 2x^2-2x-x^2+5x
=x^2+3x
5. 5-x-x^2+2-3x
=-x^2-4x+7
6. 2x+3x-4x
=x
7. 5(2x)(3x)(2y)
=60x^2 y
8. 5x(3x)+5x+3x
=15x^2+8x
1. multiply the difference of a and b by 7.
7(a-b)
2. subtract 4d from 5 times c.
5c-4d
3. add g to the product of e and f.and then multiply the sum by 8.
8(ef+g)
4. subtract 7 from 3 times h, and then divide the difference by 4 times i^2.
(3h-7)/4i^2
5. x+2x+4x
7x
6. 9-3p+7p-4
4p+5
7. 4x-2y-6x+9y
-2x+7y
8. 21y-40x+12x-9y
12y-28x
9.lucy buys r concert tickets for $1000.Express the average price of each ticket in terms of r.
1000/r
10.if a box can hold 4a oranges,express the number of oranges held by 15 boxes in terms of a.
60a
11.if the largest number among three consecutive number is x,express the sum of the three numbers in terms of x.
3x-3
之後就用列式作答
1. the calculations of the score for a general knowledge quiz is as follows:
each team has a base of 200 points.for the first round, 10 point will be given for each corract answer,and no point will be deducted for any incorrect answer or question given up.For the second round,20 point will be given for each correct answer, and 10 point will be deducted for each incorrect answer or question given up.

(a) team A answered x questions correctly in the first round. Find the score of team A after the first round.
200+10x-0
=200+10x
(b) in the second round, team A answered correctly, z questions wrongly and gave up 4 questions. Find the score of team A after these two round.
Is the question"team A answered y question correctly"?
If yes,the answer is:
200+10x+20y-10(z+4)
=200+10x+20y-10z-40
=160+10x+20y-10z

Hope I can help you.

1. 10-2x+5-3x
=10+5-2x-3x
=15-5x

2. 20-3x-30-y+4y
=20-30-3x-y+4y
=-10-3x+3y

3. 負3x+4y+5x-2y
=-3x+5x+4y-2y
=2x+2y

4. 2x^2-2x-x^2+5x
=.x^2+3x
5. 5-x-x^2+2-3x
=7-4x-x^2
6. 2x+3x-4x
=x
7. 5(2x)(3x)(2y)
=5(2y)(6x^2)
8. 5x(3x)+5x+3x
=15x^2+8x

1. 7(a-b)
2. 5c-4d
3. 8(ef+g)
4. 3x-7/4(i^2)
5. 7x
6. 5+4p
7. -2x+7y
8. 12y-28x
9.r/1000
10.15(4a)
11.3x-3

1. the calculations of the score for a general knowledge quiz is as follows:
each team has a base of 200 points.for the first round, 10 point will be given for each corract answer,and no point will be deducted for any incorrect answer or question given up.For the second round,20 point will be given for each correct answer, and 10 point will be deducted for each incorrect answer or question given up.

(a) team A answered x questions correctly in the first round. Find the score of team A after the first round.

10x points

(b) in the second round, team A answered correctly, z questions wrongly and gave up 4 questions. Find the score of team A after these two round.

200+10x-40-10x
=160points

2008-10-16 06:51:48 補充：
1. the calculations of the score for a general knowledge quiz is as follows:
each team has a base of 200 points.for the first round, 10 point will be given for each corract ...

(a) team A answered x questions correctly in the first round. Find the score of team A after the first round.

200+10x points

10分做咁多題,你都低低地@@