Answer:
x = 12
Step-by-step explanation:
Since the triangles are similar then the ratio of corresponding sides are equal, that is
[tex]\frac{4x+12}{15}[/tex] = [tex]\frac{32}{8}[/tex] = 4, thus
4x + 12 = 4 × 15 = 60 ( subtract 12 from both sides )
4x = 48 ( divide both sides by 4 )
x = 12
