e) ( 4x - 10 )2 = 25
=> ( 4x - 10 )2 = 52 = ( -5 )2
\(\Rightarrow\orbr{\begin{cases}4x-10=5\\4x-10=-5\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}4x=5+10=15\\4x=-5+10=-5\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=\frac{15}{4}\\x=\frac{-5}{4}\end{cases}}\)
f) 4x3 + 15 = 47
=> 4x3 = 47 - 15 = 32
=> x3 = 32 : 4 = 8
=> x3 = 23
=> x = 2
b) 5 . [( 16 + 88 : 86 ) : 10 + 52 ]
= 5 . [( 16 + 82 ) : 10 + 52 ]
= 5 . [( 16 + 64 ) : 10 + 52 ]
= 5 . ( 80 : 10 + 52 )
= 5 . ( 8 + 52 )
= 5 . 60
= 300
c) 16 : { 340 : [ 445 - ( 125 + 25 . 6 )]}
= 16 : { 340 : [ 445 - ( 125 + 150 )]}
= 16 . [ 340 : ( 445 - 275 )]
= 16 . ( 340 : 170 )
= 16 . 2
= 32
