Question

240x + 126y= 194,4 26x + 64y = 41,2 ????​

Answer 1

Решение.

$\left\{\begin{array}{l}\bf 240x+126y=194,4\ |:2\\\bf 26x+64y=41,2\ |:2\end{array}\right\ \ \left\{\begin{array}{l}\bf 120x+63y=97,2\\\bf 13x+32y=20,6\end{array}\right$  

Выразим из второго уравнения переменную  х и подставим в первое уравнение .

$\left\{\begin{array}{l}\bf 120\cdot \Big(-\dfrac{32}{13}y+\dfrac{20,6}{13}\Big)+63y=97,2\\\bf x=-\dfrac{32}{13}y+\dfrac{20,6}{13}\end{array}\right\\\\\\\bf 120\cdot \Big(-\dfrac{32}{13}y+\dfrac{20,6}{13}\Big)+63y=97,2\\\\\\-\dfrac{3840}{13}\, y+\dfrac{2472}{13}+63y=97,2$

$\bf -\dfrac{3021}{13}\, y=-\dfrac{2472}{13}+97,2\ \ \ ,\ \ \ -\dfrac{3021}{13}\, y=-\dfrac{1208,4}{13}$  

$\bf 3021\, y=1208,4\ \ \ ,\ \ \ y=\dfrac{1208,4}{3021}\ \ ,\ \ y=\dfrac{2}{5}=0,4$  

Найдём теперь  х .

$\bf x=-\dfrac{32}{13}\cdot 0,4+\dfrac{20,6}{13}=\dfrac{-12,8+20,6}{13}=\dfrac{7,8}{13}=0,6$  

Ответ:   $\bf \Big(\ 0,6\ ;\ 0,4\ \Big)$   .

Answer 2

Объяснение:

240х + 126у = 194,4 | * 26

26х + 64у = 41,2 | * -240

6240х + 3276у = 5054,4

-6240х - 15360у = -9888

-12084у = -4833,6

6240х + 3276у = 5054,4

1)

-12084у = -4833,6

у = -4833,6 : (-12084)

у = 0,4

2)

6240х + 3276у = 5054,4

6240х + 3276 * 0,4 = 5054,4

6240х + 1310,4 = 5054,4

6240х = 5054,4 - 1310,4

6240х = 3744

х = 3744 : 6240

х = 0,6

Ответ: (0,6; 0,4)

Answer 3

To solve the system of equations:

240x + 126y = 194.4 ...(1) 26x + 64y = 41.2 ...(2)

We can use the method of substitution or elimination to find the values of x and y.

Let's solve it using the method of elimination:

To eliminate the variable "x," we need to multiply equation (2) by 9 and equation (1) by 26:

9 * (26x + 64y) = 9 * 41.2 and 26 * (240x + 126y) = 26 * 194.4

This simplifies the equations to:

234x + 576y = 370.8 ...(3) 6240x + 3276y = 5054.4 ...(4)

Now, let's multiply equation (3) by 27 and equation (4) by 6 to create equal coefficients for y:

27 * (234x + 576y) = 27 * 370.8 and 6 * (6240x + 3276y) = 6 * 5054.4

This simplifies the equations to:

6318x + 15552y = 9990.6 ...(5) 37440x + 19656y = 30326.4 ...(6)

Now, subtract equation (5) from equation (6) to eliminate y:

(37440x + 19656y) - (6318x + 15552y) = 30326.4 - 9990.6

This simplifies to:

31122x + 4104y = 20335.8 ...(7)

Now, we have two equations with two variables:

31122x + 4104y = 20335.8 ...(7) 234x + 576y = 370.8 ...(3)

To solve this system, we can use the method of substitution. Rearrange equation (3) to solve for x:

234x = 370.8 - 576y x = (370.8 - 576y) / 234

Substitute this value of x into equation (7):

31122 * [(370.8 - 576y) / 234] + 4104y = 20335.8

Now, solve this equation to find the value of y. Once you have y, substitute it back into equation (3) or equation (5) to find the value of x.

Note: The calculations involved in solving this system of equations might result in decimals, so please ensure precision while performing the calculations.