Answer
-2
Work Step by Step
$\frac{ -3s - t - 4 }{-s + 6 + t }$
Replace s with -1 and t = -13
$\frac{ -3(-1) - (-13) - 4 }{-(-1) + 6 + (-13) }$
Do all the multiplications first
$\frac{ 3 + 13 - 4 }{1 + 6 - 13}$
Addition and subtraction from left to right the numerator and denominator
$\frac{16 - 4}{7 - 13}$ = $\frac{12}{-6}$
Dividing two numbers with the opposite sign gives negative number
-2
