348,321 views
16 votes
16 votes
If AC = 7x-3 and CB=3x+9,then find the length of AB

If AC = 7x-3 and CB=3x+9,then find the length of AB-example-1
User Avarabyeu
by
3.0k points

1 Answer

15 votes
15 votes

If AC = 7x-3 and CB=3x+9,then the length of AB is:

7x-3 + 3x +9

7x+3x -3 + 9 (Organizing)

10x + 6 (Adding like terms)

Since C is the middle point, the lenght of AC is equal to the lenght of CB, therefore we need to find the value of x with the following equation:

7x-3 = 3x+9

7x - 3x -3 = 9 ( Transposing 3x to the other side of the equation)

7x - 3x= 3 + 9 ( Transposing 3 to the other side of the equation)

4x = 12 (Adding like terms)

4/4x = 12/4 ( Dividing by 4 on both sides of the equation)

x= 3

Replacing 3 in 10x + 6, we have:

10*(3) + 6 = 30 + 6 = 36

Therefore the final answer is 36, option D.

User Kasara
by
3.1k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.