Question

3x-2y=16 x+4y=-4 способ сложения

Answer 1

X=-4+4y
3*(-4+4y)-2y=16
-12+12y-2y-16=0
10y=28
y=2,8
x=-4+4*2,8=7,2
Ответ: (7,2;2,8)

Answer 2

3х-2у=16
х+4у=-4 | *-3
3х-2у=16
-3х-12у=12
-14у=28
у=-2
3х-2*-2=16
3х=16-4
3х=12
х=4

Answer 3

To solve this system of equations using the method of addition, we need to eliminate one of the variables (either x or y) by adding the two equations together. Here's how we can do it:

First, let's multiply the second equation by 2 to get:

2(x + 4y) = 2(-4) Simplifying this equation, we get: 2x + 8y = -8

Now, we can add this equation to the first equation: 3x - 2y + 2x + 8y = 16 - 8 Simplifying this equation, we get: 5x + 6y = 8

Now we have one equation with only x and y in it. We can solve for one of the variables (let's choose y) and substitute the result back into one of the original equations to solve for the other variable.

5x + 6y = 8 6y = 8 - 5x y = (8 - 5x)/6

Now, we can substitute this expression for y into one of the original equations (let's use the first one): 3x - 2((8-5x)/6) = 16

Simplifying this equation, we get: 15x - 24 = 96 15x = 120 x = 8

So the solution to the system of equations is x = 8 and y = (8-5x)/6, or y = -1.