Respuesta :

Answer:

y = 14

Step-by-step explanation:

If a line is parallel to a side of a triangle and it intersects the other two sides then it divides those sides proportionally , that is

[tex]\frac{y}{21}[/tex] = [tex]\frac{10}{15}[/tex] = [tex]\frac{2}{3}[/tex] ( cross- multiply )

3y = 42 ( divide both sides by 3 )

y = 14

mhanifa

Answer:

  • C) 14

Step-by-step explanation:

Parallel lines divide the transversals proportionally.

Set proportions and solve for y:

  • y/(y + 21) = 10/(10 + 15)
  • y / (y + 21) = 10/25
  • y / (y + 21) = 2/5
  • 5y = 2(y + 21)
  • 5y = 2y + 42
  • 5y - 2y = 42
  • 3y = 42
  • y = 14

Correct choice is C