1。 Express the equivalence relation in the following questions, and then solve the equation.
(1) There are 36 willows in the park. Poplar is twice as big as willow. How many poplars and willows are there?
Poplar+willow = total number solution: there are x willows.
2x+x=36
3X=36
X=36/3
X= 12
(2) The house should be paved with square bricks. With a square brick with a side length of 3 m, 96 yuan is needed. If you replace it with a square brick with an area of 4 square decimeters, how many pieces are needed at least?
The area of a brick multiplied by the number of bricks needed = area.
Solution: Assume that at least x blocks are needed.
4X=3 times 3 times 96.
4X=9 times 96
4X=864
X=864\4
X=2 16
The lightest bird in the world is the hummingbird. A hummingbird weighs 2. 1 g, and a sparrow loses weight 1 g, which is exactly 50 times that of this hummingbird. How much does this sparrow weigh?
The weight of a hummingbird+1 times 50= the weight of a sparrow.
Solution: make this sparrow weigh x grams.
X- 1=2. 1 times 50.
X- 1= 105
X= 105+ 1
X= 106
2. Solve the equation
6X-X=75 Y+3Y=24.4 3X-8=25
Solution 5X=75 solution 4Y=24.4 solution 3X=25+8.
X=75/5 Y=24.4/4 3X=33
X= 15 Y=6. 1 X=33/3
X= 1 1
X/6=3.5 8+8X=88
Solution X=3.5 times 6 solution 8X=88-8.
X=2 1 8X=80
X=80/8
X= 10