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YOUR ANSWER: The sentence 4 + 3 != 9 is false.
Now, wait a minute. You know that in english we can make true statements that are positive assertions and we can also make true statements that are negative assertions. Consider these simple statements of fact:
(1) Fire is hot.
(2) Fire is not cold.
The first is a positive statement, and the second is a negative statement, and both of these statements are true.
Now, we can make both true positive and true negative assertions in mathematics just as we can in english. When we make a positive assertion that we claim to be true, we use, for example, the equals sign:
4 + 3 = 7
This is a true statement according to the accepted meanings of the symbols 4, 3, and 7, because both sides of the equation have the same value.
To make a negative assertion that is mathematically true, we use the not-equal sign:
4 + 3 != 9
This is likewise a true statement, according to the accepted meanings of the symbols 4, 3, and 9, because both sides of the "equation" do not have the same value and that's exactly what the sentence says: Four plus three is not equal to nine.
Now return to page 11 and choose the correct answer.