Respuesta :

lolslimes07
Answer:

a+7

Step-by-step explanation:

2 + 5 = 7
7+a or a+7
fatma39

Answer:

a=-7

Step-by-step explanation:

first we do commutative property of real number

the expression becomes ;

2+(7+a)=

then association property follow-up

(2+7)+a=

7+a=

then we minus 7 to both sides

7-7+a=-7

0+a=-7

a=-7