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## #1 2023-11-15 03:49:57

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Real Solutions of the Quadratic Equation...A

Show that the real solutions of the equation ax^2 + bx + c = 0 are the negatives of the real solutions of the equation ax^2 - bx + c = 0. Assume that b^2 - 4ac is greater than or equal to 0.

I don't even know where to begin. I welcome any hints.

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## #2 2023-11-15 04:10:37

amnkb
Member
Registered: 2023-09-19
Posts: 175

### Re: Real Solutions of the Quadratic Equation...A

sologuitar wrote:

Show that the real solutions of the equation ax^2 + bx + c = 0 are the negatives of the real solutions of the equation ax^2 - bx + c = 0. Assume that b^2 - 4ac is greater than or equal to 0.

Last edited by amnkb (2023-11-15 04:34:37)

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## #3 2023-11-16 18:20:00

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Re: Real Solutions of the Quadratic Equation...A

amnkb wrote:
sologuitar wrote:

Show that the real solutions of the equation ax^2 + bx + c = 0 are the negatives of the real solutions of the equation ax^2 - bx + c = 0. Assume that b^2 - 4ac is greater than or equal to 0.

How did you know what to do? What data in the application led you to work out the problem as you did?

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## #4 2023-11-17 17:21:26

KerimF
Member
From: Aleppo-Syria
Registered: 2018-08-10
Posts: 53

### Re: Real Solutions of the Quadratic Equation...A

sologuitar wrote:

How did you know what to do? What data in the application led you to work out the problem as you did?

As you know, to compare two solutions, one just needs to find each of them first.

But in the case of someone who didn't hear yet the solution (root’s formula) of a quadratic equation, the proof will be much longer.

For instance, I forgot the math trick by which the root’s formula was found (when I was at school about 60 years ago), so now I needed to search “How to find the quadratic equation formula” to remember it Offline

## #5 2023-11-18 03:59:10

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Re: Real Solutions of the Quadratic Equation...A

KerimF wrote:
sologuitar wrote:

How did you know what to do? What data in the application led you to work out the problem as you did?

As you know, to compare two solutions, one just needs to find each of them first.

But in the case of someone who didn't hear yet the solution (root’s formula) of a quadratic equation, the proof will be much longer.

For instance, I forgot the math trick by which the root’s formula was found (when I was at school about 60 years ago), so now I needed to search “How to find the quadratic equation formula” to remember it Keep all your math tricks to yourself. Get involved in the conversation by providing your math work and less lectures.

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