Substitution Property of Equality: If a=20, then 5a= _____.

Question

The substitution rule states that If a=b then a can be substituted for b in any equation or expression.

So I think that 5a=5b but the number answer is 100. Am I correct?

Answer 1

correct.

But your reasoning is skewed. Forget about some "b". Substitute 20 for a.

5a = 5(20) = 100

Answer 2

But is 5a equal to 5b?

Answer 3

only if a=b

Answer 4

Yes a is equal to b. Thanks for your help!

Answer 5

If 2n=6, what property of equality is justified