The required 1st term and third term in the given expressions are -3x and -12pqr
Expressions are mathematical equations separated by signs.
For instance, a + b + c is an expression having three terms
First-term is a
Second term is "b"
Third term is "c"
Given the expression -3x + 7, we are to identify the first term. Based on the explanation above, the first term will be - 3x
For the expression 9pq - 3pr - 12pqr, the third term from this equation will be -12pqr
Hence the required 1st term and third term in the given expressions are -3x and -12pqr
Learn more here: https://brainly.com/question/17499155
