Toán (x+1)+(x+2)+(x+3)+….+(x+10)=57 giúp mình với iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii 10/09/2021 By Lyla (x+1)+(x+2)+(x+3)+….+(x+10)=57 giúp mình với iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
$\text{(x + 1) + (x + 2) + (x + 3) + … + (x + 10) = 57}$ $\text{x × 10 + (1 + 2 + 3 + … + 10) = 57}$$\text{x × 10 + 55 = 57}$$\text{x × 10 = 57 – 55}$$\text{x × 10 = 2}$$\text{x = 2 : 10}$$\text{x = 0,2}$ Trả lời
(x+1)+(x+2)+(x+3)+….+(x+10) = 57 ⇔ x + 1 + x + 2 + x + 3 +…..+ x + 10 = 57 ⇔ 10x + ( 1 + 2 + …… + 10 ) = 57 ⇔ 10x + 55 = 57 ⇔ 10x = 2 ⇒ x = 0,2 Trả lời
$\text{(x + 1) + (x + 2) + (x + 3) + … + (x + 10) = 57}$
$\text{x × 10 + (1 + 2 + 3 + … + 10) = 57}$
$\text{x × 10 + 55 = 57}$
$\text{x × 10 = 57 – 55}$
$\text{x × 10 = 2}$
$\text{x = 2 : 10}$
$\text{x = 0,2}$
(x+1)+(x+2)+(x+3)+….+(x+10) = 57
⇔ x + 1 + x + 2 + x + 3 +…..+ x + 10 = 57
⇔ 10x + ( 1 + 2 + …… + 10 ) = 57
⇔ 10x + 55 = 57
⇔ 10x = 2
⇒ x = 0,2