Question

If D_y = $-$ 15 and D = $-$ 5 are the values of the determinant for certain simultaneous equation in x and y, find y.

Answer 1

$$\begin{gathered} \mathrm{We}\mathrm{know}\mathrm{that} \\ y=\frac{{\mathrm{D}}_{\mathrm{y}}}{\mathrm{D}} \\ \Rightarrow y=\frac{-15}{-5} \\ \therefore y=3 \end{gathered}$$