7xy − 3xz + yz + 3xy − 5xz ​+ 4yz?

7xy - 3xz + yz + 3xy - 5xz + 4yz equals 10xy - 8xz + 5yz.

−42x+3 +​ 5 ?

-42x + 3 + 5 equals -42x + 8.

`-4\left(2x+3\right)\ +\ 5\ ?`

-4(2x + 3) + 5 equals -8x - 12 + 5, which simplifies to -8x - 7.

1 3​9x+​15

1/3(9x + 15) can be simplified to 3x + 5.

1​0−x−3

10 - x - 3 simplifies to 7 - x.

`10-\left(x-3\right)`