Answer to Question #236235 in Math for luka

Question

Using a =(3,4) and b=(2,-1) as base vectors, express the vector C =(7,2) in form ya+ub

Answer 1

$xa+yb=c$

$3x+2y=7$

$4x-y=2$

$x=1,y=2$

So, $c=a+2b$