Question

solve x(x + 5) = 0

Answer 1

If something multiplied by something is zero, then one of those things must be 0. In the context of solving an equation like this, you can set both parts equal to 0 and solve.

Answer 2

hint:

if

A*B = 0

then

A = 0 or B = 0

Answer 3

yes. x squared
+ 5x = 0

Answer 4

You don't want to distribute, Luke. That just sets you back a step.

Answer 5

Not at all..

Answer 6

i have to solve for x right?

Answer 7

Young Jeezy, if A*B = 0, then either A or B must be 0, yes? So x(x+5) is the same as A*B.

Answer 8

Yes, you are trying to solve for x.

Answer 9

which is A and which is B?

Answer 10

It doesn't matter. A*B = 0 is just a rule. You can make x be the A and (x+5) be the B or visa versa. The rule is just to help you understand that from here, to solve for x, you have to set both parts equal to zero, then solve.

Answer 11

I'll give you a hint that may help clear up some confusion: there are TWO answers to for x in this problem. Not just one.

Answer 12

then the answer is + - a square root of a number

Answer 13

Not necessarily. There are other ways you can have two answers.

Answer 14

Take both parts of the equation you have left, the X and the X+5, and set each one to zero. o x = 0 and x+5 = 0. Then try solving.

Answer 15

is the answer square root of 5 and negative square root of 5?

Answer 16

No, it's not. You are one step away from solving it. Don't try to mess with the x(x+5). That's what you need. Now take each factor (the x and the x+5) and separately set them equal to 0. Then solve.

Answer 17

if x=0 then i can substitute x in the x+5=0 equation, or no?

Answer 18

No, once you split them apart to solve, they become "separate" equations. Solve each one on its own.

Answer 19

well, x=0, isnt that already solved?

Answer 20

Yep

Answer 21

But this problem has more than one answer, as I said before.

Answer 22

so if x+5=0,i have to leave x by itself. so it would become x= -5

Answer 23

Yes sir. So x = 0, -5

Answer 24

i got it! thank you so much. i really needed to know this.

Answer 25

Just remember, if you ever have "something" multiplied by "something else" and it's equal to zero, you can solve that by setting each different factor equal to zero and solving.

Answer 26

And there CAN BE more than one answer!

Answer 27

i get it now :) thanks for the help

Answer 28

No problem.