Axioms of equality are basic rules for using the equals sign…
The Additive Axiom Of Equality:
If a=b and c=d, then a+c=b+d.
The Additive Axiom Of Inequality:
If a>b, then a+c>b+c.
Identity Element For Addition:
Any number added to 0 gives the original number, for instance, n+0=n.
Identity Element For Multiplication:
Any number multiplied by 1 gives the original number, for instance, n*1=n.
Multiplicative Axiom Of Equality:
If a=b and c=d, then ac=bd.
Negative Multiplication Property Of Inequality:
You must reverse the inequality sign when multiplying or dividing by a negative number.
Firstly you have to know what (a+b+c)(d+e+f) is. You can expand this expression using a rectangle:
So you know that:
Next you’d have to multiply (a+b+c)(d+e+f) by (g+h+i) using another rectangle:
And from here you’d figure out that: