Question

7x – 2y =15x - 3y = 7​

Answer 1

ОТВЕТ:
x=-1
y=-4


ОБЪЯСНЕНИЕ:

Answer 2

The given system of equations is:

1. 7x - 2y = 7
2. 15x - 3y = 7

We can use the method of substitution or elimination to solve this system. I'll use the elimination method here.

First, let's multiply both sides of equation (1) by 3 to make the coefficients of y in both equations equal:

1. 3(7x - 2y) = 3(7) 21x - 6y = 21

Now, we have the system:

1. 21x - 6y = 21
2. 15x - 3y = 7

Next, let's multiply equation (2) by 2 to make the coefficients of y in both equations equal:

2. 2(15x - 3y) = 2(7) 30x - 6y = 14

Now, we have the system:

1. 21x - 6y = 21
2. 30x - 6y = 14

Now, we can subtract equation (1) from equation (2) to eliminate the variable y:

(30x - 6y) - (21x - 6y) = 14 - 21

This simplifies to:

9x = -7

Now, divide both sides by 9 to solve for x:

x = -7 / 9

Now that we have the value of x, we can substitute it back into equation (1) to solve for y:

21x - 6y = 21 21(-7/9) - 6y = 21

Now, simplify:

-147/9 - 6y = 21

Multiply both sides by 9 to isolate -6y:

-147 - 54y = 189

Now, add 147 to both sides:

-54y = 189 + 147 -54y = 336

Finally, divide both sides by -54 to solve for y:

y = -336 / -54 y = 56/9

So, the solution to the system of equations is:

x = -7/9 y = 56/9