(s-3)²
(s-4s)²
(20m-21d)²
(y-z)²
(4-5p)²
(x-10z)²
(s-3)² =
(s-3)(s-3) =
s.s - 3.s -3.s + 3.3 =
s² - 6s + 9
(s-4s)² =
(s-4s)(s-4s) =
s.s - s.4s - s.4s + 4s.4s =
s² - 4s² - 4s² + 16s² =
s² - 8s² + 16s² =
9s²
(20m-21d)² =
(20m - 21d)(20m - 21d) =
20m.20m - 21d.20m - 21d.20m + 21d.21d =
400m² - 420md - 420md + 441d² =
400m² - 840md + 441d²
(y-z)² =
(y - z)(y - z) =
y.y - y.z - y.z + z.z =
y² - 2yz + z²
(4-5p)² =
(4 - 5p)(4 - 5p) =
4.4 - 4.5p - 4.5p + 5p.5p =
16 - 20p - 20p + 25p² =
25p² - 40p + 16
(x-10z)² =
(x - 10z)(x - 10z) =
x.x - x.10z - x.10z + 10z.10z =
x² - 10zx - 10zx + 100z² =
x² - 20zx + 100z²
Comments
(s-3)² =
(s-3)(s-3) =
s.s - 3.s -3.s + 3.3 =
s² - 6s + 9
(s-4s)² =
(s-4s)(s-4s) =
s.s - s.4s - s.4s + 4s.4s =
s² - 4s² - 4s² + 16s² =
s² - 8s² + 16s² =
9s²
(20m-21d)² =
(20m - 21d)(20m - 21d) =
20m.20m - 21d.20m - 21d.20m + 21d.21d =
400m² - 420md - 420md + 441d² =
400m² - 840md + 441d²
(y-z)² =
(y - z)(y - z) =
y.y - y.z - y.z + z.z =
y² - 2yz + z²
(4-5p)² =
(4 - 5p)(4 - 5p) =
4.4 - 4.5p - 4.5p + 5p.5p =
16 - 20p - 20p + 25p² =
25p² - 40p + 16
(x-10z)² =
(x - 10z)(x - 10z) =
x.x - x.10z - x.10z + 10z.10z =
x² - 10zx - 10zx + 100z² =
x² - 20zx + 100z²