Sagot :
for all real numbers a,b,c and d, if a=b and c=d, then a+c = b+d.
Addition Property of Equality was used in solving algebraic expression. For example:
x-10=25
x-10+10=25+10 (A.P.E)
x=35
x-10=25
x-10+10=25+10 (A.P.E)
x=35