Answer:
The critical numer is x = -3/10
Step-by-step explanation:
We need to find the derivative of the function and then equal to zero to get the values of x.
The function is:
[tex]f(x)=10x^{2}+6x[/tex]
Let's take the derivative whit respect of x and equal to zero.
[tex]f'(x)=20x+6[/tex]
[tex]0=20x+6[/tex]
Now, we just need to solve it for x.
[tex]x=-\frac{3}{10}[/tex]
The critical numer is x = -3/10
I hope it helps you!