Question

Найдите корни уравнения (без дискриминанта ) : 1) (x - 7)^2 - 49 = 0 2) (6 + y)^2 - 81 = 0

Answer 1

$\sf\displaystyle (x-7)^2-49=0\\(x-7)^2=49\\\left [{ {{x-7=7} \atop {x-7=-7}} \right. \left [{ {{x=14} \atop {x=-0}} \right.$

ответ: $0;14$

$\displaystyle \sf (6+y)^2-81=0\\(y+6)^2=81\\\left [{ {{y+6=9} \atop {y+6=-9}} \right. \left [{ {{y=3} \atop {y=-15}} \right.$

ответ: $-15;3$

Answer 2

1)(x-7)²=49

x-7=±√49

x-7=±7⇒x1=14,x2=0.

2)(6+y)²=81

6+y=±√81

6+y=±9 ⇒y1=3,y2=-15.