Answer:
The value of x is 7.5 in.
Explanation:
Consider the provided information.
Let the length of the box is x in, width 6 in and height is 5 in.
The Volume of the box is:
![length* width* height](https://img.qammunity.org/2019/formulas/mathematics/middle-school/vq8q8q8tik7q2977rpx8hmaputswb5ftbl.png)
![Volume=x* 6* 5](https://img.qammunity.org/2019/formulas/mathematics/middle-school/xe0bj0z9d7vxzez41wh9lrfg5mq5jm19ga.png)
![Volume=30x](https://img.qammunity.org/2019/formulas/mathematics/middle-school/7k5lcqwwesbb8pf6at29d7gzmvecnj5183.png)
The surface area of rectangle is:
SA = 2[(length×width)+(width×height)+(length×height)]
SA = 2[(6×x)+(6×5)+(x×5)]
SA = 2[6x+30+5x]
SA = 2[11x+30]
It is given that surface area is equal to the value of the solids volume.
30x = 2[11x+30]
15x = 11x+30
4x = 30
x = 30/4
x = 7.5
Hence, the value of x is 7.5 in.