Answer:
Step-by-step explanation:
Set up the following ratio which applies to all angle bisectors and the side opposite.
8 / (x + 4) = 12 / (2x + 1) Cross multiply
8 * (2x + 1) = 12 * (x + 4)
16x + 8 = 12x + 48 Subtract 8 from both sides
16x + 8 -8 = 12x + 48-8
16x = 12x + 40 Subtract 12x from both sides
16x - 12x = 40
4x = 40 Divide by 4
4x/4 = 40/4
x = 10
