Solve a^2 - 7a - 30 = 0

Results 1 to 6 of 6

- Jun 17th 2018, 10:41 AM #1

- Joined
- Jun 2018
- From
- Home
- Posts
- 11

- Jun 17th 2018, 11:06 AM #2

- Jun 17th 2018, 11:09 AM #3

- Joined
- Jun 2018
- From
- Home
- Posts
- 11

- Jun 17th 2018, 11:10 AM #4

- Joined
- Jun 2018
- From
- Home
- Posts
- 11

- Jun 17th 2018, 11:51 AM #5

- Jun 18th 2018, 04:58 AM #6

- Joined
- Apr 2005
- Posts
- 19,934
- Thanks
- 3098

## Re: More to come from me !! It’s been a while

The basic point in solving problems like this is the "zero product property": "if ab= 0 then either a= 0 or b= 0". Once you have that $\displaystyle (a- 10)(a+ 3)= 0$ then we must have either $\displaystyle a- 10= 0$ or $\displaystyle a+ 3= 0$. That gives, of course, two different values for a either of which satisfies the original equation.