I don't really understand and I need help.

see explanation

Step-by-step explanation:

Expressing the rule in the form y = mx + b

where m is the slope and b the y- intercept

Calculate m using the slope formula

m = (y₂ - y₁ ) / (x₂ - x₁ )

with (x₁, y₁ ) = (2, 1) and (x₂, y₂ ) = (4, 0) ← 2 ordered pairs from the table

m = = = - , thus

y = - x + b ← is the partial equation

To find b substitute any ordered pair into the partial fraction

Using (4, 0), then

0 = - 2 + b ⇒ b = 0 + 2 = 2

y = - x + 2 ← function rule

answer: it's d

step-by-step explanation: