Find the value of [tex]x[/tex] if [tex]A[/tex], [tex]B[/tex], and [tex]C[/tex] are collinear points and [tex]B[/tex] is between [tex]A[/tex] and [tex]C[/tex].

Given:
[tex]AB = 5[/tex],
[tex]BC = 3x + 7[/tex],
[tex]AC = 5x - 2[/tex]

A. 7
B. 6
C. 14
D. 12



Answer :

To solve for [tex]\( x \)[/tex], we need to use the fact that points [tex]\( A \)[/tex], [tex]\( B \)[/tex], and [tex]\( C \)[/tex] are collinear, and point [tex]\( B \)[/tex] is between [tex]\( A \)[/tex] and [tex]\( C \)[/tex].

Given:
[tex]\[ AB = 5 \][/tex]
[tex]\[ BC = 3x + 7 \][/tex]
[tex]\[ AC = 5x - 2 \][/tex]

Since point [tex]\( B \)[/tex] is between [tex]\( A \)[/tex] and [tex]\( C \)[/tex], the total length [tex]\( AC \)[/tex] can be expressed as the sum of the segments [tex]\( AB \)[/tex] and [tex]\( BC \)[/tex]:
[tex]\[ AB + BC = AC \][/tex]

Substituting the given lengths into this equation:
[tex]\[ 5 + (3x + 7) = 5x - 2 \][/tex]

Next, combine the constants and the terms involving [tex]\( x \)[/tex]:
[tex]\[ 5 + 3x + 7 = 5x - 2 \][/tex]

Simplify the left side of the equation:
[tex]\[ 12 + 3x = 5x - 2 \][/tex]

To isolate the variable [tex]\( x \)[/tex], move all terms involving [tex]\( x \)[/tex] to one side of the equation and constants to the other:
[tex]\[ 12 + 2 = 5x - 3x \][/tex]

Simplify both sides:
[tex]\[ 14 = 2x \][/tex]

Solve for [tex]\( x \)[/tex]:
[tex]\[ x = \frac{14}{2} = 7 \][/tex]

So, the value of [tex]\( x \)[/tex] is [tex]\( 7 \)[/tex].

Thus, the correct answer is:
[tex]\[ \boxed{7} \][/tex]