Question

7x-10y=20
-7x-2y=4

Answer 1

I think you can solve this.
"add" the two equations together to solve for y by elimination.
Once you get the value of y, put that in to one of the equations and solve for x.

Let me know if you need any help.

Answer 2

you can use either elimination or subsitution

Answer 3

\(\Large \begin{cases} 7x-10y=20\ \ \ (1)\\-7x-2y=4\ \ \ (2) \end{cases} \)
(1)+(2) \(\Large \Rightarrow -12y=24 \\\Large \Rightarrow y=\frac{24}{-12}=-2\)

From (1) \(\Large \Rightarrow x=\frac{20+10y}{7}=\frac{20-20}{7}=0\)

Answer 4

7x-10y=20 .....(1)

-7x-2y=4 .....(2)
Add both the equations, we get
-12y = 24
or y = -2

Put y = -2 in equation (1)
7x - 10 * -2 = 20
7x + 20 = 20
7x = 0
x =0
The set of solution is (0, -2).

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