(х+3)²=100
√(х+3)²=√100
х+3=10
х=10-3
х=7
(х+3)×2=100
х+3=100÷2
х+3=50
х=50-3
х=47
(47+3)×2=100
100=100
(х+3)²=100
√(х+3)²=√100
х+3=10
х=10-3
х=7
(х+3)×2=100
х+3=100÷2
х+3=50
х=50-3
х=47
(47+3)×2=100
100=100