Hello!
The answers are:
1
![p=3](https://img.qammunity.org/2020/formulas/mathematics/high-school/1qxrfxrwm9p8xzcktelp4nzrdrcpc307j3.png)
2
![x=-7](https://img.qammunity.org/2020/formulas/mathematics/middle-school/qp7m9sktqywwjsmtkve39iyj6rs8mn21w9.png)
3
![x=35](https://img.qammunity.org/2020/formulas/mathematics/middle-school/behvpftvyx7yzmq25vfxib6rqtd3uby11v.png)
4
![x=7](https://img.qammunity.org/2020/formulas/mathematics/high-school/5ymgceaqbtxby47vkmnw7y964ourmheca5.png)
Why?
To know the solution of the problems, we need to isolate each variable.
Remember that:
- If we have an equality: if the number is part of a product , and if you need to move it to the other side of the equality, the same number will be dividing the factors of the side.
- If we have an equality: if the number is subtracting (negative sign), and if you need to move it to the other side of the equality, its sign changes to positive.
- If we have an equality: if the number is adding (positive sign), and if you need to move it to the other side of the equality, its sign changes to negative.
- The distributive property states that:
![a(b+c)=ab+ac](https://img.qammunity.org/2020/formulas/mathematics/high-school/v6t9nm9vizrtf6zbqqtkhhv6na97chl3l1.png)
So,
1 - Solving for p
![2(p+5)=16\\2p+10=16\\2p=16-10=6\\p=(6)/(2)=3](https://img.qammunity.org/2020/formulas/mathematics/middle-school/9sat25w2ijjv09fizz4ledc2vck2v8zo6t.png)
2 - Solving for t
![-3(t+1)=18\\-3t-3=18\\-3t=18+3=21\\t=(21)/(-3)=-7](https://img.qammunity.org/2020/formulas/mathematics/middle-school/rdlj1fajtrh01dhap4aoi7xo42kn4ju1jv.png)
3 - Solving for x
![-(2)/(5)(x-10)=-10\\-(2)/(5)x+(2)/(5) *10=-10\\-(2)/(5)x+4=-10 \\-(2)/(5)x=-10-4=-14\\-(2)/(5)x=-14\\x=(-14)/((-2)/(5) )=14*(5)/(2)=35](https://img.qammunity.org/2020/formulas/mathematics/middle-school/922o8iyr8w5vga9ih5w8wth6cq15zyeudn.png)
4 - Solving for x
![(2)/(3)(x-10)=-2\\\\x-10=(-2)/((2)/(3) )=-2*(\\3)/(2)\\\\x-10=-3\\x=-3+10\\x=7](https://img.qammunity.org/2020/formulas/mathematics/middle-school/9degxcy3emvca0zevly0cm8tbof99689qd.png)
Have a nice day!