Tìm x (1+2+3+....+50)x=2+4+6+....+100

2 câu trả lời

`(1+2+3+....+50)x=2+4+6+....+100`

`<=>(1+2+3+....+50)x=2626`

`<=>1275x=2550`

`<=>x=2`

Vậy `x=2`

`(1 +2 +3 +...+50).x = 2 +4 +6 +100`

`⇒ [50.(50 +1)]/2.x = [50.(100 +2)]/2`

`⇒ 1275.x = 2550`

`⇒ x = 2550 : 1275`

`⇒ x = 2`

`Vậy` `x = 2`