Which axiom would justify the following conclusion? If x + 4 = 12, then x = 8.

Solution:

Given, x + 4 = 12 and x = 8

We have to justify which axiom will conclude x = 8

Using addition,

x + 4 = 12

Use x = 8

8 + 4 = 12

Thus, addition concludes x + 4 = 12 when x = 8.

Using subtraction,

x + 4 = 12

Use x = 8

8 - 4 ≠ 12

Thus, subtraction cannot be the answer.

Using multiplication, the sum is too much.

Therefore, addition can only be the axiom to follow the given conclusion.

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Which axiom would justify the following conclusion? If x + 4 = 12, then x = 8.

Summary:

The axiom that would justify the following conclusion if x + 4 = 12, then x = 8 is addition.