Writing Vector <1,7> as Sum of 2 Vectors

[Loppyfoot]

Homework Statement

Write the vector <1,7> as a sum of two vectors, one parallel to <2,-1> and one perpendicular to <2,-1>

Homework Equations

DOt Product

The Attempt at a Solution

I'm confused on where to begin this problem. Should I be using the dot product?

Thanks

 

[weesiang_loke]

i think you should draw out the vectors as they make up a right angle triangle.

 

[Loppyfoot]

I got the answer:

<-2,1> and <3,6>