I’ll give brainliest!

Answer:
y = -x + 4
Step-by-step explanation:
y = mx + b
m - since the line is going downwards. the slope is negative
slope = rise / run = 1 / 1 = 1 but negatuve siunce diwnawards
b - this the y - intercept (when x = 0), the point of intersect is (0, 4)