I took a picture of the work instead ^^
The solution is 
<em><u>Solution:</u></em>
Let us assume,

<em><u>Given system of equations are:</u></em>


<em><u>Rewrite the equation using "a" and "b"</u></em>
2a - 3b = -5 ------------ eqn 1
4a + 6b = 14 -------------- eqn 2
<em><u>Let us solve eqn 1 and eqn 2</u></em>
<em><u>Multiply eqn 1 by 2</u></em>
2(2a - 3b = -5)
4a - 6b = -10 ------------- eqn 3
<em><u>Add eqn 2 and eqn 3</u></em>
4a + 6b = 14
4a - 6b = -10
( - ) --------------------
8a = 4

Substitute a = 1/2 in eqn 1

Now let us go back to our assumed values
Substitute a = 1/2 in assumed values

Substitute b = 2 in assumed value

Thus the solution is 
The first pipe fills 1/8 of a pool in one hr.
The second pipe fills 1/4 of a pool in one hr.
(1/8+1/4)2= 3/4 done by the first two pipes in 2 hours.
Therefore the last pipe must do 1 1/4 of the filling in 2 hours, which is 5/8 per hour.
5/8x=1
x=8/5
It takes the third pipe 1 hour and 36 minutes to fill it by itself.
Answer:
1296000 seconds
Step-by-step explanation:
Hope this helps