Question

8x – 9y – 21 = 0,3x – 2y - 12 = 0.​

Answer 1

Ответ:

8x – 9y – 21 = 0

8x – 9y – 21 +21=0+21

8x – 9y =0+21

8x – 9y=21

3x – 2y - 12 = 0

3x – 2y-12+12=0+12

3x – 2y=0+12

3x – 2y=12

Answer 2

8x-9y-21=0 |*3
3x-2y-12=0 |*(-8)

24x-27y-63=0
-24x+16y+96=0

8x-9y-21=0
-11y+33=0

8x-9y=21
y= 3

8x=21+27
y=3

8x=48
y=3

x=6
y=3

Answer 3

You have a system of two linear equations with two variables, x and y:

1. 8x - 9y - 21 = 0
2. 3x - 2y - 12 = 0

You can solve this system of equations using various methods, such as substitution, elimination, or matrix methods. Let's use the elimination method to solve it.

First, we can multiply the second equation by 4 to make it easier to eliminate one of the variables:

1. 8x - 9y - 21 = 0
2. 12x - 8y - 48 = 0

Now, let's subtract the second equation from the first equation to eliminate y:

(8x - 9y - 21) - (12x - 8y - 48) = 0

This simplifies to:

8x - 9y - 21 - 12x + 8y + 48 = 0

Now, combine like terms:

(8x - 12x) + (-9y + 8y) + (-21 + 48) = 0

Simplify further:

-4x - y + 27 = 0

Now, you have a new equation:

3. -4x - y + 27 = 0

Now, you have a system of two equations:

1. 8x - 9y - 21 = 0
2. -4x - y + 27 = 0

You can solve this system of equations by substitution or elimination. Let's use the elimination method again.

First, multiply the third equation by 9 to make it easier to eliminate y:

3. -4x - y + 27 = 0 (Multiply by 9) -36x - 9y + 243 = 0

Now, add the first equation and the modified third equation to eliminate y:

(8x - 9y - 21) + (-36x - 9y + 243) = 0

Combine like terms:

(8x - 36x) + (-9y - 9y) + (-21 + 243) = 0

Simplify:

-28x - 18y + 222 = 0

Now, you have a new equation:

4. -28x - 18y + 222 = 0

Now, you have a system of two equations:

1. 8x - 9y - 21 = 0
2. -28x - 18y + 222 = 0

You can continue to solve this system of equations using either the elimination method or another method of your choice.