Question

Tìm x,biết :(x+1)+(x+2)+(x+3)+...+(x+1000)=5750

Answer 1

(x + 1) + (x + 2) + (x + 3) + ... + (x + 1000) = 5750

<=> 100x + (1 + 2 + 3 + ... + 100) = 5750

<=> 100x + (1 + 100) x 50 = 5750

<=> 100x + 101 x 50 = 5750

<=> 100x + 5050 = 5750

<=> 100x = 5750 - 5050

<=> 100x = 700

<=> x = 7

Answer 2

thank you bạn nha