For exercises 1–6, factor the expanded form of these quadratic expressions. pay particular attention to the negative and
positive signs.
1. 3x^2 − 2x − 8
2. 3x^2 + 10x − 8
3. 3x^2 + x − 14 [notice that there is a 1 as a coefficient in this one.]
4. 2x^2 − 21x − 36 [this might be a challenge. if it takes too long, try the next one.]
5. −2x^2 + 3x + 9 [this one has a negative on the leading coefficient.]
6. + 6
4 + 9
16 [we need to try one with fractions, too.]
for exercises 7–10, use the structure of these expressions to factor completely.
7. 100x^2 − 20x −63
8. y^4 + 2y^2 − 3
9. 9x^2 − 3x − 12
10. + − 6

Apsychology student wishes to investigate differences in political opinions between business majors and political science majors at her college. she randomly selects 100 students from the 260 business majors and 100 students from the 180 political science majors. does this sampling plan result in a simple random sample? why or why not? no, because each group of 200 students in the sample does not have the same chance of being selected. yes, because each group of 200 students in the sample has the same chance of being selected. no, because each individual student does not have an equal chance of being selected. yes, because each individual student has the same chance of being selected.