SOLUTION: Help I'm stuck. Triangles ABC and triangle DEF are similar. what is the length of line DF? line AC=4 ,line BC=2,line EF=7

Algebra ->  Triangles -> SOLUTION: Help I'm stuck. Triangles ABC and triangle DEF are similar. what is the length of line DF? line AC=4 ,line BC=2,line EF=7      Log On


   

Question 133446: Help I'm stuck. Triangles ABC and triangle DEF are similar. what is the length of line DF?
line AC=4 ,line BC=2,line EF=7
Found 2 solutions by scott8148, josmiceli:
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the triangles are similar, so the ratio of the corresponding sides is constant

AC%2FDF=BC%2FEF __ 4%2FDF=2%2F7 __ "cross" multiplying __ 28=2DF

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The ratios of corresponding sides is the same
AB/DE = BC/EF = AC/DF
You can use any part or all of these ratios
to solve problems
line AC=4 ,line BC=2,line EF=7
Find line DF
BC/EF = 2/7
AC/DF = 4/DF
AC/DF = BC/EF
4/DF = 2/7
Solve for DF
4/DF = 4/14
DF = 14 answer