Finding unknown length of a similar rectangle

[ilovemath333]

Hello, it's been an incredibly long time since I've done geometry and I was having trouble helping my son with his homework. It's difficult finding a simple explanation for this type of stuff online so I was hoping to find some help here. How would you find the unknown length in this problem? Is there a formula to apply? And what should the correct answer be?

 

[Deleted member 4993]

View attachment 23767

Hello, it's been an incredibly long time since I've done geometry and I was having trouble helping my son with his homework. It's difficult finding a simple explanation for this type of stuff online so I was hoping to find some help here. How would you find the unknown length in this problem? Is there a formula to apply? And what should the correct answer be?

Please tell your son to look up the definition of "similar rectangles". If you & him are still stuck, please come back and tell us the definition and exactly where you are stuck

 

[Steven G]

Suppose the 70 was instead 112 (note 56*2=112). Would you be able to do the problem then? How would you do it? Maybe you can use the same method with the numbers given in the diagram? Post back showing your progress.