初中数学优秀教案大集合（Junior high school mathematics, excellent lesson plans large collection）
Topic: equation of two variables
I. teaching objectives:
1. understand the concept of the solution of the two variables one equation and the two variables equation;
2., learn to find out the solution of a certain two yuan equation, and test whether a pair of values is the solution of the two yuan equation once;
3. learn to express an unknown number in the equation of two variables in a form of another unknown;
4., in the process of solving the problem, we should infiltrate the thought and method of analogy and permeate the moral education
Two, teaching key points and difficulties:
Emphasis: the meaning of the equation of two variables and the concept of the solution of the two variables equation
Difficulty: the deformation of a two dollar one equation into a form of another unknown by means of an algebraic expression of an unknown. The essence of it is to solve an equation containing the letter coefficients
Three, teaching methods and teaching methods:
By comparing with the one yuan one equation, we can strengthen the students' thinking methods of analogy. Through cooperative learning, we can make the students realize that mathematics is based on the actual needs
Four, teaching process:
1. scenario introduction:
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Equation is obtained: 80a+150b=902 880.
2. new curriculum teaching:
Guiding students to observe the equation 80a+150b=902 880 is different from the one yuan one equation
The concept of two yuan one equation: the equation that contains two unknowns and the number of terms of the unknown number is 1 times is called the two yuan one equation
Do sth.:
(1) problem according to the equation:
Xiao Ming went to visit grandma and bought 5 kg apples and 3 kg pears. They spent 23 yuan, respectively, for the price of
apples and pears. The price of the apples was X Yuan /kg, and the price of pears was y yuan /kg;
In the highway, a car traveling at 2 distance than a truck driving 3 distance more than 20 kilometers, if the car speed is a km / hour, the speed of the truck is B km / h, equations can be obtained.
(2) P80。