Question

What does y equal? ​

Answer 1

Answer:

$y=-4x+17$

Step-by-step explanation:

$\begin{pmatrix}4&1\end{pmatrix}\quad \mathrm{and}\quad \begin{pmatrix}2&9\end{pmatrix}$

$\mathrm{Computing\:dot\:product\:of\:two\:vectors}:\quad \left(x_1,\:\:\ldots ,\:\:x_n\right)\cdot \left(y,\:\:\ldots ,\:\:y_n\right)=\sum _{i=1}^nx_iy_i$

$=4\cdot \:2+1\cdot \:9$

$=17$