# Find a vector's component given that the vector is perpendicular to another vector [closed]

What value of $$a$$ makes vector $${\bf u} = (a,1)$$ perpendicular to $${\bf v} = (3,2)$$?

• Welcome to Mathematics Stack Exchange. Set the dot product $\vec u \cdot \vec v$ to be $0$ – J. W. Tanner Nov 24 '19 at 0:32
• Thank you. Alright I got it . – aita.kane Nov 24 '19 at 0:37

If $$\vec u$$ and $$\vec v$$ are perpendicular, then $$\vec u\cdot\vec v=0$$.
Thus $$(a,1)\cdot(3,2)=3a+2=0$$.