x^2-5x-36 =0
=》(×+4)(x-9) =0
=》 x = 9 or -4
positive solution for x is 9
For this case we must find the positive solution of the following quadratic equation:
[tex]x ^ 2-5x-36 = 0[/tex]
To find the solutions we factor, that is, we look for two numbers that when multiplied give as result -36 and when summed give as result -5.
These are:
-9 and +4
[tex]-9 * 4 = -36\\-9 + 4 = -5[/tex]
So, we have:
[tex](x-9) (x + 4) = 0[/tex]
The roots are:
[tex]x_ {1} = 9\\x_ {2} = - 4[/tex]
The positive solution is 9.
Answer:
9