$(x-1{)}^2-9=0$
$(x-1{)}^2-3^2=0$
(x − 1 − 3)(x − 1 + 3) = 0
(x − 4)(x + 2) = 0
x − 4 = 0
x = 4
или
x + 2 = 0
x = −2
Ответ: −2 и 4

$81-(y+1{)}^2=0$
$9^2-(y+1{)}^2=0$
(9 − (y + 1))(9 + y + 1) = 0
(9 − y − 1)(y + 10) = 0
(8 − y)(y + 4) = 0
8 − y = 0
y = 8
или
y + 10 = 0
y = −10
Ответ: −10 и 8

$(x+2{)}^2-36=0$
$(x+2{)}^2-6^2=0$
(x + 2 − 6)(x + 2 + 6) = 0
(x − 4)(x + 8) = 0
x − 4 = 0
x = 4
или
x + 8 = 0
x = −8
Ответ: −8 и 4

$100-(y-7{)}^2=0$
${10}^2-(y-7{)}^2=0$
(10 − (y − 7))(10 + y − 7) = 0
(10 − y + 7)(y + 3) = 0
(17 − y)(y + 3) = 0
17 − y = 0
y = 17
или
y + 3 = 0
y = −3
Ответ: −3 и 17