An item costs `x` dollars and then a 20% discount is applied. b) Sam says that 20/100x` will not work. Do

Step-by-step explanation:

Cost of item = x

Percentage discount = 20%

Discount on item :

20% * x

20/100 * x

0.2x

Cost of item after discount :

Initial cost - discount

x - 0.2x

0.8x

step-by-step explanation: s

answer: -10

step-by-step explanation:

s(t) = 1 - 10t

s(x) = 1 - 10x

s(x + h) = 1 - 10(x + h)

            = 1 - 10x - 10h

s(x + h) - s(x) = 1 - 10x - 10h - (1 - 10x)

                      = 1 - 10x - 10h - 1 + 10x

                      = -10h

= -10