Respuesta :

Answer:

7

Step-by-step explanation:

basically just subtract 10-3=7 then to check 3+7=10

Answer:

x = 7

Step-by-step explanation:

3 + x = 10

-3         -3

x = 7

you subtract by 3 on both sides (because the opposite property of addition is subtraction) to cancel it out and isolate the x.