Question

3x +4y = -20 5x + 2y = -10

Answer 1

Ответ:

3х+4у=-20

5х+2у=-10 /× -2

3х+4у=-20

-10х-4у=20

-7х=0

х=0

3×0+4у=-20

4у=-20

у=-20÷4

у=-5

х = 0

у = -5

Answer 2

It looks like you've provided a system of linear equations with two variables, x and y. To solve for the values of x and y, you can use methods like substitution or elimination. Let's use the elimination method in this case:

Given the system of equations:

1. $3x + 4y = -20$
2. $5x + 2y = -10$

We'll multiply both sides of equation 1 by 5 and equation 2 by 3 to make the coefficients of x in both equations the same. This will allow us to eliminate x by subtracting one equation from the other:

Multiplying equation 1 by 5: $15x + 20y = -100$

Multiplying equation 2 by 3: $15x + 6y = -30$

Now, subtract the second equation from the first equation to eliminate x:

$(15x + 20y) - (15x + 6y) = -100 - (-30)$ $14y = -70$

Divide both sides by 14: $y = -5$

Now that we have the value of y, we can substitute it into one of the original equations to solve for x. Let's use equation 1:

$3x + 4(-5) = -20$ $3x - 20 = -20$ $3x = 0$ $x = 0$

So, the solution to the system of equations is $x = 0$ and $y = -5$.