1.)

-9 + 4r = 4r - 3 - 6

2.)

6x - 2x + 8 = x + 5

3.)

4n + 5n + 15 = 5n + 7n

-9 + 4r = 4r - 3 - 6

0 = 0

6x - 2x + 8 = x + 5
4x + 8 = x + 5
3x = 5 - 8
3x = -3
x = ?

I'll be glad to check your answer for the last problem.

on the last one its the only one that i didn't get the others im just checking if i got them right.

I'm sorry you didn't post your answers to the first two problems.

oh sorry i forgot.

To solve these equations, we need to isolate the variable on one side of the equation.

1.) -9 + 4r = 4r - 3 - 6

First, let's simplify both sides of the equation. Combine like terms on each side:

-9 + 4r = 4r - 9

Now, let's eliminate the 4r term on the right side of the equation. We can do this by subtracting 4r from both sides of the equation:

-9 + 4r - 4r = 4r - 9 - 4r

Simplifying further, we have:

-9 = -9

This equation is true for all values of r. So, there is no specific solution for r. The equation has infinitely many solutions.

2.) 6x - 2x + 8 = x + 5

First, let's simplify both sides of the equation. Combine like terms on each side:

4x + 8 = x + 5

Next, let's eliminate the x term on the right side of the equation. We can do this by subtracting x from both sides of the equation:

4x + 8 - x = x + 5 - x

Simplifying further, we have:

3x + 8 = 5

Now, let's isolate the x term on one side of the equation. We can do this by subtracting 8 from both sides of the equation:

3x + 8 - 8 = 5 - 8

Simplifying further, we have:

3x = -3

Finally, let's solve for x by dividing both sides of the equation by 3:

(3x)/3 = (-3)/3

Simplifying further, we have:

x = -1

So, the solution for x is -1.

3.) 4n + 5n + 15 = 5n + 7n

First, let's simplify both sides of the equation. Combine like terms on each side:

9n + 15 = 12n

Next, let's eliminate the 9n term on the left side of the equation. We can do this by subtracting 9n from both sides of the equation:

9n - 9n + 15 = 12n - 9n

Simplifying further, we have:

15 = 3n

Now, let's isolate the n term on one side of the equation. We can do this by subtracting 15 from both sides of the equation:

15 - 15 = 3n - 15

Simplifying further, we have:

0 = 3n - 15

Finally, let's solve for n by adding 15 to both sides of the equation:

3n - 15 + 15 = 15 + 15

Simplifying further, we have:

3n = 30

Now, let's solve for n by dividing both sides of the equation by 3:

(3n)/3 = 30/3

Simplifying further, we have:

n = 10

So, the solution for n is 10.