Factor the following
(y-1)^2-4

(y - 3)(y + 1)

Step-by-step explanation:

Given

(y - 1)² - 4 ← this is a difference of squares and factors in general as

a² - b² = (a - b)(a + b), thus

(y - 1)² - 4

= (y - 1)² - 2²

= (y - 1 - 2)(y - 1 + 2)

= (y - 3)(y + 1) ← in factored form

sss (side, side, side)

sas (side, angle, side)

asa (angle, side, angle)

aas (angle, angle, side)

hl (hypotenuse, leg)