Need to calculate: The value of F(10) for the function F(x)=begin{cases}2x if x<3 -5x if xgeq 3 end{cases}

Formula used:
Some functions are defined by different equations for various parts for their domains.
Those functions are called piecewise-defined functions.
To solve the piecewise-defined function for an input, we will determine that which part of the domain it belongs to and use the appropriate formula for that part of the domain.
Calculation:
Consider the provided function,
$F(x)=\{\begin{array}{l}2xifx<3\\ -5xifx\ge 3\end{array}$
The function provided is defined in multiple equations.
Therefore, to determine F(10) identify in which equation 10 will lie.
10 lies in the interval $x\ge 3$. Therefore, to determine the value of F (10), $F(x)=-5x$ will be used.
Substitute $x=10$ into the equation $F(x)=-5x$.
$F(x)=-5x$
$F(-1)=-5\ast (10)=-50$
Hence, the value of F (10) is -50.