Answer:
Inequality:
![25x + 50 \leq\ 225](https://img.qammunity.org/2021/formulas/mathematics/college/17hrj0c7jompnozcqhwro34m8hz3an1nm2.png)
Number of Friends: At most 6
Explanation:
Given
![Concert = \$ 25](https://img.qammunity.org/2021/formulas/mathematics/college/lgz36wqi9x4drbyl366p65xr9vejtkoqbl.png)
![Food\ and\ Shirts= \$50](https://img.qammunity.org/2021/formulas/mathematics/college/wjjv36dasr6694zxprzasyvfyyi84xlggn.png)
![Amount = \$225](https://img.qammunity.org/2021/formulas/mathematics/college/dsp7vadsi9kgqt2y1827mky8r4hd6rabxk.png)
Solving (a): Inequality
Let the number of friends including Jessica be represented by x
Per individual, the concert is 25
For x individuals, the concert is 25x
Since she will be spending at most 225,
the inequality can be represented as:
![25x + 50 \leq\ 225](https://img.qammunity.org/2021/formulas/mathematics/college/17hrj0c7jompnozcqhwro34m8hz3an1nm2.png)
Solving (b): Number of friends
This implies that we solve for x in (a) above
![25x + 50 \leq\ 225](https://img.qammunity.org/2021/formulas/mathematics/college/17hrj0c7jompnozcqhwro34m8hz3an1nm2.png)
![25x \leq\ 225 - 50](https://img.qammunity.org/2021/formulas/mathematics/college/yedfpn2z1dsbnt40jc6do5q2s6yapo5wtu.png)
![25x \leq\ 175](https://img.qammunity.org/2021/formulas/mathematics/college/awamm579nsujn2x1fy3nekzfdnnjappgl3.png)
Divide through by 25
![x \leq\ 175/25](https://img.qammunity.org/2021/formulas/mathematics/college/bda6zombaq5wdm00s35zrlzl8i3b8blwbl.png)
![x \leq\ 7](https://img.qammunity.org/2021/formulas/mathematics/college/nf9u0pu5yh96nsiwm6fir07xsnxxj2i91v.png)
Since the value of x above also include Jessica;
This implies that she will be able to bring at most 6 friends