Bài tập  /  Bài đang cần trả lời

Giải bài có thưởng!

Tìm x, biết: 2|2x - 3| - 1 = 5

a) 2 l2x-3l - 1 = 5 
b)15 - 2 l3x+1l=7
c)4 l3x-2l + 5 = 17 
d)23 - 3 l7x-1l=2
 
0 trả lời
Hỏi chi tiết
40
Tham khảo câu trả lời từ Trợ lý ảo Lazi
a) 2|2x-3| - 1 = 5
To solve this equation, we need to isolate the absolute value term.
First, we add 1 to both sides of the equation:
2|2x-3| = 6
Next, we divide both sides by 2:
|2x-3| = 3
Now, we have two cases to consider:
1) 2x-3 = 3
Solving for x, we add 3 to both sides:
2x = 6
Dividing both sides by 2:
x = 3
2) -(2x-3) = 3
Expanding the negative sign:
-2x + 3 = 3
Subtracting 3 from both sides:
-2x = 0
Dividing both sides by -2:
x = 0
Therefore, the solutions to the equation are x = 3 and x = 0.

b) 15 - 2|3x+1| = 7
To solve this equation, we need to isolate the absolute value term.
First, we subtract 7 from both sides of the equation:
-2|3x+1| = -8
Next, we divide both sides by -2:
|3x+1| = 4
Now, we have two cases to consider:
1) 3x+1 = 4
Solving for x, we subtract 1 from both sides:
3x = 3
Dividing both sides by 3:
x = 1
2) -(3x+1) = 4
Expanding the negative sign:
-3x - 1 = 4
Adding 1 to both sides:
-3x = 5
Dividing both sides by -3:
x = -5/3
Therefore, the solutions to the equation are x = 1 and x = -5/3.

c) 4|3x-2| + 5 = 17
To solve this equation, we need to isolate the absolute value term.
First, we subtract 5 from both sides of the equation:
4|3x-2| = 12
Next, we divide both sides by 4:
|3x-2| = 3
Now, we have two cases to consider:
1) 3x-2 = 3
Solving for x, we add 2 to both sides:
3x = 5
Dividing both sides by 3:
x = 5/3
2) -(3x-2) = 3
Expanding the negative sign:
-3x + 2 = 3
Subtracting 2 from both sides:
-3x = 1
Dividing both sides by -3:
x = -1/3
Therefore, the solutions to the equation are x = 5/3 and x = -1/3.

d) 23 - 3|7x-1| = 2
To solve this equation, we need to isolate the absolute value term.
First, we subtract 23 from both sides of the equation:
-3|7x-1| = -21
Next, we divide both sides by -3:
|7x-1| = 7
Now, we have two cases to consider:
1) 7x-1 = 7
Solving for x, we add 1 to both sides:
7x = 8
Dividing both sides by 7:
x = 8/7
2) -(7x-1) = 7
Expanding the negative sign:
-7x + 1 = 7
Subtracting 1 from both sides:
-7x = 6
Dividing both sides by -7:
x = -6/7
Therefore, the solutions to the equation are x = 8/7 and x = -6/7.

Bạn hỏi - Lazi trả lời

Bạn muốn biết điều gì?

GỬI CÂU HỎI
Học tập không giới hạn cùng học sinh cả nước và AI, sôi động, tích cực, trải nghiệm

Hôm nay bạn thế nào? Hãy nhấp vào một lựa chọn, nếu may mắn bạn sẽ được tặng 50.000 xu từ Lazi

Vui Buồn Bình thường

Học ngoại ngữ với Flashcard

×
Gia sư Lazi Gia sư
×
Trợ lý ảo Trợ lý ảo