If the area of the triangle formed by the image of the first-order function y = - 2x + B and the two coordinate axes is equal to 4, the analytic expression of the function is obtained

If the area of the triangle formed by the image of the first-order function y = - 2x + B and the two coordinate axes is equal to 4, the analytic expression of the function is obtained

According to the meaning of the title
The intercept of the function on the Y axis is | B|
Let the intersection of function and X axis be (a, 0)
Then we substitute it into the equation
-2a+｜b｜=0
a=｜b｜/2
Then s (area) = a * b * 0.5 = B ^ / 4 = 4
So B = ± 4
So the analytic expression of the function is
Y = - 2x + 4 or y = - 2X-4