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1 vote
3x+2y=11
7x-y=3
Using substitution or elimination method

User Dread
by
6.9k points

2 Answers

5 votes

\left\{\begin{array}{ccc}3x+2y=11\\7x-y=3&|multiply\ both\ sides\ by\ 2\end{array}\right\\+\underline{\left\{\begin{array}{ccc}3x+2y=11\\14x-2y=6\end{array}\right}\ \ \ |add\ both\ sides\ of\ equations\\. \ \ \ \ \ \ 17x=17\ \ \ \ |divide\ both\ sides\ by\ 17\\.\ \ \ \ \ \ \ \boxed{x=1}\\\\Put\ the\ value\ of\


Answer:\boxed{\boxed{ \left\{\begin{array}{ccc}x=1\\y=4\end{array}\right}}
User Lew Bloch
by
7.6k points
1 vote
Just use elimination
Steps:
1. Multiply everything in the system 7x-y=3 by 2
2. New systems are
3x + 2y=11
14x-2y=6
3. 2y + -2y= 0 so y cancels itself out
4. 14x+ 3x=17x
11 + 6=17
5. New problem is
17x=17
6. Divide each side by 17
7. Your answer is x=1
8. Now substitute the x in 7x-y=3 for 1
7(1)-y=3
7-y=3
9. Subtract 7 on both sides
-y=-4
10. Divide by -1
y=4
User Sudhanshu Gupta
by
7.0k points