Answer:
Vijay is 6 and Sushma is 21.
Explanation:
Let's set up a system of equations for this question.
Let S be Sushma's age and V be Vijay's age.
![S = 15 + V](https://img.qammunity.org/2021/formulas/mathematics/college/jm5qxd7t9jd65jj1f3bx3ntgeumdkaf6gz.png)
![S + 3 = 8(V - 3)](https://img.qammunity.org/2021/formulas/mathematics/college/7ciot2d31xnpj04stypm5kozosu1otq0cx.png)
Manipulate the second equation to isolate S:
![S + 3 = 8(V - 3)](https://img.qammunity.org/2021/formulas/mathematics/college/7ciot2d31xnpj04stypm5kozosu1otq0cx.png)
![S + 3 = 8V - 24](https://img.qammunity.org/2021/formulas/mathematics/college/m3av757r9adksu7f48rbns9y5nl12p3smm.png)
![S = 8V - 24 - 3](https://img.qammunity.org/2021/formulas/mathematics/college/kmn2c579fn3gh8azowz6taszpvce3y73au.png)
![S = 8V - 27](https://img.qammunity.org/2021/formulas/mathematics/college/a50ake2ctgnblmo9did90i0h84y29ct0eh.png)
Plug in the second equation into the first:
![8V - 27 = 15 + V](https://img.qammunity.org/2021/formulas/mathematics/college/jv0ocv3c9sbs32yno7jmyr5o5mwdsyc3pl.png)
![8V - V = 15 + 27](https://img.qammunity.org/2021/formulas/mathematics/college/we6eby5dw86aq6foa94j4de2g4qedk2dri.png)
![7V = 42](https://img.qammunity.org/2021/formulas/mathematics/college/qvicge1ibfpa1ixpihhkv8hhfhofo8vd10.png)
![V = 6](https://img.qammunity.org/2021/formulas/physics/college/c91hgjq3ekp5s3ab7bue99rhltmwmopff2.png)
![S = 15 + V](https://img.qammunity.org/2021/formulas/mathematics/college/jm5qxd7t9jd65jj1f3bx3ntgeumdkaf6gz.png)
![S = 21](https://img.qammunity.org/2021/formulas/mathematics/college/7cs0wc8su3y1bti4cgxys42h9bt3684m6r.png)
Hope this helped!