Question

Afla valoarea lui "y" din expresia: y-(1+2+3+...+48)=3520.
Va rod, repede! Funda si puncte

Answer 1

y - ( 1+2+3+...+48) = 3520
( 1+2+2+...+48) =
n = ( 48 - 1 ) : ( 2-1) +1
n = 47 : 1 +1
n = 47 + 1
n = 48
S = [( 48 +1) x 48 ] : 2
S = ( 49 x 48) : 2
S = 2352 : 2
S = 1176.
y - 1176 = 3520
y = 3520 + 1176
y = 4696.

Answer 2

y-48*49/2=3520

y-24*49=3520

y-1176=3520

y=3520+1176

y=4696