Toán a, 149-4.(x+25)=49 b, [ 2.(x+5)-31].4=52 19/07/2021 By Melody a, 149-4.(x+25)=49 b, [ 2.(x+5)-31].4=52
Đáp án: `149-4.(x+25)=49` ` 4.(x+25)=149-49` `4.(x+25)=100` ` x+25=100:4` `x+25=25` ` x=25-25` `x=0` `[ 2.(x+5)-31].4=52` `[2.(x+5)-31]=52:4` `[2.(x+5)-31]=13` `2.(x+5)=13+31` `2.(x+5)=44` `(x+5)=44:2` `(x+5)=22` `x+5=22-5` `x=17` Trả lời
Đáp án: ` 149 – 4(x+25) = 49` ` => -4(x+25) = 100` ` => x +25 = -25` ` => x = -25-25` ` => x = -50` Vậy ` x = -50` ***** ` [ 2(x+5) – 31] . 4 = 52` ` => [2 (x+5) – 31] = 13` ` => 2(x+5) = 13 +31` ` => 2(x+5) = 44` ` => x +5 = 22` ` => x= 17` Trả lời