![\bf \begin{cases} \boxed{y}=-2x\\\\ -x-y=4 \end{cases} \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{since we know what \boxed{y} is, let's substitute it in the 2nd equation}}{-x-\left( \boxed{-2x} \right)=4\implies -x+2x=4\implies x=4} \\\\[-0.35em] ~\dotfill\\\\ y=-2x\implies y=-2(4)\implies y=-8 \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ ~\hfill (4,-8)~\hfill](/tpl/images/0016/0499/47055.png)
Can someone explain how to do this ?
...
Answers: 1
Another question on Mathematics
Mathematics, 21.06.2019 17:30
What is not true about kl and mn? what is mn? (show your work)
Answers: 1
Mathematics, 21.06.2019 20:30
Arectangle has a width of 5 cm and a length of 10 cm. if the width is increased by 3, how does the perimeter change?
Answers: 1
Mathematics, 21.06.2019 23:50
If the tip varies directly with the number of guest which equation represents between the tip,t, and the number of guest,g?
Answers: 1
You know the right answer?
Questions
Social Studies, 28.09.2019 08:30
English, 28.09.2019 08:30
Physics, 28.09.2019 08:30
Chemistry, 28.09.2019 08:30
Physics, 28.09.2019 08:30
Mathematics, 28.09.2019 08:30
Mathematics, 28.09.2019 08:30
Mathematics, 28.09.2019 08:30
Computers and Technology, 28.09.2019 08:30
Chemistry, 28.09.2019 08:30
Chemistry, 28.09.2019 08:30
