SOLUTION: I was looking on a website that teaches linear algebra and it had this problem: (3x - 15)/(2x + 1) = 0 And it says the answer is: x = 5 But I don't understand how to get t

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Question 476118: I was looking on a website that teaches linear algebra and it had this problem:
(3x - 15)/(2x + 1) = 0
And it says the answer is: x = 5
But I don't understand how to get that answer so I was hoping someone can give me step by step directions for it.
Found 2 solutions by ankor@dixie-net.com, richard1234:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
%283x+-+15%29%2F%282x+%2B+1%29 = 0
multiply both sides by (2x+1)
(2x+1)*%283x+-+15%29%2F%282x+%2B+1%29 = (2x+1)*0
Cancel the denominator on the left, the right is 0
3x - 15 = 0
Add 15 to both sides
3x = 15
Divide both sides by 3
x = 15%2F3
x = 5
:
:
See if that works in the original equation
%283%285%29+-+15%29%2F%282%285%29+%2B+1%29 = 0
%2815+-+15%29%2F%2810+%2B+1%29 = 0
0%2F11 = 0, (0 divided by any number is 0)

Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
This doesn't look like linear algebra...linear algebra deals with matrices, determinants, vector spaces, and so on.

Anyway, we set the numerator to zero, i.e. set 3x - 15 = 0. Solving for x we get x = 5. We want to make sure the denominator is nonzero so we can plug in x = 5 into the denominator. The denominator is nonzero, so x = 5 works.