Practice problem
Solve the following system of linear equations. {21x−7y=−42−4x+2y=4\begin{cases} 21x-7y=-42\\ -4x+2y=4 \end{cases}{21x−7y=−42−4x+2y=4
(2,6)(2,6)(2,6)
(−1,0)(-1,0)(−1,0)
(−2−2)(-2-2)(−2−2)
(−4,−6)(-4,-6)(−4,−6)
Type a concept, like “slope” or “photosynthesis”.
