Given:
The system of equations is
![5g+4k=10](https://img.qammunity.org/2021/formulas/mathematics/high-school/o6nwml2tnsfdlpetfenjqloiwqvl49huu6.png)
![-3g-5k=7](https://img.qammunity.org/2021/formulas/mathematics/high-school/zuobt6bjgb6cyn0wnfz6knoholu385uco2.png)
To find:
The solution of given system of equations.
Solution:
We have,
...(i)
..(ii)
Multiply (i) by 5 and (ii) by 4.
...(iii)
..(iv)
Adding (iii) and (iv), we get
![25g-12g=50+28](https://img.qammunity.org/2021/formulas/mathematics/high-school/7m5hhbxbhr2nzxnctsbxfs3l3czicku5tw.png)
![13g=78](https://img.qammunity.org/2021/formulas/mathematics/high-school/sbwvy7yurukuj5k669ucywaknainc6ta5h.png)
Divide both sides by 13.
![g=(78)/(13)](https://img.qammunity.org/2021/formulas/mathematics/high-school/zu3spf079k69ltyumg75piodk8bnpog042.png)
![g=6](https://img.qammunity.org/2021/formulas/mathematics/high-school/dnpxjvhzk3ig7lh0wgrwlm6wvjajeo6ja2.png)
Put g=6 in (i).
![5(6)+4k=10](https://img.qammunity.org/2021/formulas/mathematics/high-school/z9pmdjs4z46l7911q1ft1nz7av7d5j6dc5.png)
![30+4k=10](https://img.qammunity.org/2021/formulas/mathematics/high-school/rytca37jlvbhgmyexzyzlp66uujwynjutx.png)
![4k=10-30](https://img.qammunity.org/2021/formulas/mathematics/high-school/93isb27oljx4l5exunlo8g39ug0btuv6vw.png)
![4k=-20](https://img.qammunity.org/2021/formulas/mathematics/high-school/jbcu8v4gh5r8rm7dd83drc7h3xo98bxjje.png)
Divide both sides by 4.
![k=-5](https://img.qammunity.org/2021/formulas/mathematics/middle-school/6arx1uekdwvawv3lo4qz16kswqu3s24x5u.png)
So, the solution of the system of equation is (6,-5).
Therefore, the correct option is A.