Question

B is between A and C if AB=3x+4 and BC= 4x-1 and AC=8x+15, find BC

Answer 1

BC =
`\begin{vmatrix}- 49\end{vmatrix}` = 49 unit

Explanation:

The given as AC is a line with B as its mid point

AND ,

AC = 8x + 15

AB = 3x + 4

BC = 4x - 1

∵ AC = AB + BC

Or, 8x + 15 = ( 3x + 4 ) + ( 4x - 1)

Or, 8x + 15 = 7x + 3

Or, 8x - 7x = 3 - 15

∴ x = - 12

SO, AC = 8x + 15 = 8 × ( - 12) + 15 = - 81

Or, AC =
`\begin{vmatrix}- 81\end{vmatrix}` = 81 unit

And ,AB = 3x + 4 = 3 × ( - 12) + 4 = - 32

Or ,AB =
`\begin{vmatrix}- 32\end{vmatrix}` = 32 unit

Similarly BC = 4x - 1 = 4 × ( - 12) - 1 = - 49

Or, BC =
`\begin{vmatrix}- 49\end{vmatrix}` = 49 unit Answer