( 2^2 + 1 ) ( x + 14 ) = 5^2 * 4 + ( 2^5 + 3^2 + 7^2 ) :2
Ta có :
52 . 4 + ( 25 + 32 + 72 ) : 2
= 25 . 4 + ( 32 + 9 + 49 ) : 2
= 100 + 90 : 2
= 100 + 45
= 145
⇒ ( 22 + 1 ) . ( x + 14 ) = 145
⇒ ( 4 + 1 ) . ( x + 14 ) = 145
⇒ 5 . ( x + 14) = 145
⇒ x + 14 = 145 : 5
⇒ x + 14 = 29
⇒ x = 29 - 14
⇒ x = 15
Vậy x = 15
Ta có: \(\left(2^2+1\right)\left(x+14\right)=5^2\cdot4+\left(2^5+3^2+7^2\right):2\)
\(\Leftrightarrow5\cdot\left(x+14\right)=100+45=145\)
\(\Leftrightarrow x+14=29\)
hay x=15
(22+1).(x+14)=52.4+(25+32+72):2
(4+1).(x+14)=25.4+(32+9+49):2
5.(x+14)=100+90:2
5.(x+14)=55
x+14=55:5=11
x=11-14=-3