X+y=36。
25×2x=40y
The solution is x= 16.
y=20
5. Solution: A cart and a car can transport X tons and Y tons respectively at one time.
2x+3y= 15.5。
5x+6y=35
The solution is x=4.
y=2.5
So 4×3+2.5×5=24.5 (ton)
6. solution: let the uphill distance from a to b be x km and the flat road distance be y km.
Then x+ y= 54/60.
5 x+ 4 y= 24/60。
The solution is x= two thirds.
Y= eight fifths
7. Solution: Suppose that X kilograms of disinfectant containing 30% drugs and Y kilograms of disinfectant containing 75% drugs are needed.
X+y= 18。
30%x+75%y= 18×50%
The solution is x= 10.
y=8
8. Solution: We assume that before the discount, each commodity of commodity A is X yuan, and each commodity of commodity B is Y yuan. According to the meaning of the question, you will get.
60x+30y= 1080
50x+ 10y=840
The solution is x= 16.
y=4
A: It's cheaper than no discount, 400 yuan.
9. Solution: X yuan for each toothbrush and Y yuan for each box of toothpaste.
39x+2 1y=396
52x+28y=5 18
The system of equations has no solution, so this record is wrong.
It must be correct, the textbook is completely solved! ! !
Despise sneak attack! !
References:
Complete solution of teaching materials
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Report |20 10-04-23 12:39 Waiting for the lonely snow in spring | Level 1
4. Solution: The box body is made of X pieces of iron and the bottom of the box is made of Y pieces of iron, which can make the box body and the bottom of the box just match.
X+y=36。
25×2x=40y
The solution is x= 16.
y=20
5. Solution: A cart and a car can transport X tons and Y tons respectively at one time.
2x+3y= 15.5。
5x+6y=35
The solution is x=4.
y=2.5
So 4×3+2.5×5=24.5 (ton)
6. solution: let the uphill distance from a to b be x km and the flat road distance be y km.
Then x+ y= 54/60.
5 x+ 4 y= 24/60。
The solution is x= two thirds.
Y= eight fifths
7. Solution: Suppose that X kilograms of disinfectant containing 30% drugs and Y kilograms of disinfectant containing 75% drugs are needed.
X+y= 18。
30%x+75%y= 18×50%
The solution is x= 10.
y=8
8. Solution: We assume that before the discount, each commodity of commodity A is X yuan, and each commodity of commodity B is Y yuan. According to the meaning of the question, you will get.
60x+30y= 1080
50x+ 10y=840
The solution is x= 16.
y=4
A: It's cheaper than no discount, 400 yuan.
9. Solution: X yuan for each toothbrush and Y yuan for each box of toothpaste.
39x+2 1y=396
52x+28y=5 18