If s (x) = 2 - x and f (x) = 3x, which value is equivalent to (s f) (-7)

Step-by-step explanation:

the first method:

s (x) = 2 - x and f (x) = 3x

(s f) (-7) = s (-7) * f (-7)

but : s (-7) = 2 - (-7) = 2+7 = 9

f (-7) = 3 (-7) = - 21

so : (s f) (-7) = (9) * (-21) = - 189

the second method:

calculate : (s f) (x) = = s (x) * f (x) = (2-x) 3x = 6x - 3x²

(s f) (-7) = 6 (-7) - 3 (-7) ² = - 42 - 147 = - 189