Question

Равносильные уравнения. Линейное уравнение с одной переменной. Решение линейных уравнений с одной переменной. Урок 3 Классный руководитель приобрел 25планшетов для учащихся своего класса, стоимостью по 15000 тг для мальчиков и по 10000 тг для девочек. Если известно, что сумма потраченных денег для мальчиков и для девочек одинаковая, то сколько девочек в этом классе? ​

Answer 1

Ответ:

15

Пошаговое объяснение:

хз просто понел

Answer 2

Ответ:

Пошаговое объяснение:

Answer 3

Linear Equations with One Variable

A linear equation with one variable is an equation that can be written in the form ax + b = 0, where a and b are constants and x is the variable. The goal is to find the value of x that satisfies the equation.

To solve a linear equation with one variable, we can use various methods such as:

1. Isolation of the variable: This involves isolating the variable on one side of the equation by performing inverse operations. For example, if we have the equation 3x - 5 = 10, we can isolate x by adding 5 to both sides and then dividing by 3: 3x = 15 → x = 5.

2. Substitution: This method involves substituting the value of one variable in terms of another variable. For example, if we have the equation 2x + 3y = 10 and we know the value of y, we can substitute it into the equation and solve for x.

3. Elimination: This method involves eliminating one variable by adding or subtracting equations. For example, if we have the system of equations: - 2x + 3y = 10 - 4x - 2y = 6 We can eliminate y by multiplying the first equation by 2 and the second equation by 3, and then subtracting the two equations to eliminate y. We can then solve for x and substitute the value of x back into one of the original equations to find the value of y.

Now let's apply these methods to solve the given problem.

Solving the Problem

The class teacher purchased 25 tablets for the students in their class. The tablets cost 15,000 tenge for boys and 10,000 tenge for girls. If the total amount spent on boys and girls is the same, we need to determine the number of girls in the class.

Let's assume the number of boys in the class is b and the number of girls is g. We can set up the following equation based on the given information:

15000b = 10000g

To solve this equation, we can use the method of isolation of the variable. Dividing both sides of the equation by 10000, we get:

1.5b = g

This equation tells us that the number of boys is 1.5 times the number of girls. Since the number of students in the class is 25, we can write another equation:

b + g = 25

Now we have a system of equations:

1.5b = g b + g = 25

We can solve this system of equations using the elimination method. Multiplying the second equation by 1.5, we get:

1.5b + 1.5g = 37.5

Subtracting the first equation from this equation, we can eliminate g:

1.5b + 1.5g - 1.5b = 37.5 - 0

Simplifying, we find:

1.5g = 37.5

Dividing both sides by 1.5, we get:

g = 25

Therefore, there are 25 girls in the class.

Conclusion

Based on the given information, the class teacher purchased 25 tablets for the students in their class. The tablets cost 15,000 tenge for boys and 10,000 tenge for girls. Since the total amount spent on boys and girls is the same, there are 25 girls in the class.