Question

x+4x+7x+.......+58x=596

tìm x

Answer 1

Ta có : x + 4x + 7x + ...... + 58x = 596

<=> x(1 + 4 + 7 + ...... + 58) = 596

=> x 590 = 596

=> x = 596/590

Answer 2

x + 4x + 7x + ..... + 58x = 596

( x + 4x + 7x + ...+58x) = 596

( x + 58x) x [( 58x - x ) : 3 + 1 ] : 2 =     596

x = 590 = 596

x = 596 : 590

x = 596/590