Question

35.7Найти корни уравнений 2) (6+y)^2-81=0; 4)25- (13+t)^2=0

Answer 1

36+2у-81=0
2у=81-36
2у=35
у=14,5

25+168+2t=0
2t=-168-25
2t=-193
t=-96,5

Answer 2

2) (6+y)^2-81=0

(6+y)^2-9^2=0

(6+y-9)(6+y+9)=0

(y-3)(15+y)=0

y=3 или y=-15

4)25- (13+t)^2=0

5^2-(13+t)^2=0

(5-13-t)(5+13+t)=0

(-8-t)(18+t)=0

t=-8 или t=-18