After a brief hiatus, the Algebra 2 Problems of the Day are back. Hopefully, daily.
More Algebra 2 problems.
January 2019, Part II
All Questions in Part I are worth 2 credits. Partial credit can be earned.
27. Erin and Christa were working on cubing binomials for math homework. Erin believed they could
save time with a shortcut. She wrote down the rule below for Christa to follow.
Does Erin’s shortcut always work? Justify your result algebraically.
Answer:
Erin's shortcut does not work.
Substituting non-zero numbers will show this. However, that method will not receive full credit because the question stated "algebraically".
(a + b)3
= (a + b)(a + b)(a + b)
= (a + b)(a2 + ab + ab + b2)
= (a + b)(a2 + 2ab + b2)
= (a3 + 2a2b + ab2 + ba2b + 2ab2 + b3)
= (a3 + 3a2b + ab2 + 3ab2 + b3)
=/= a3 + b3
28. The probability that a resident of a housing community opposes spending money for community
improvement on plumbing issues is 0.8. The probability that a resident favors spending money
on improving walkways given that the resident opposes spending money on plumbing issues is
0.85. Determine the probability that a randomly selected resident opposes spending money on
plumbing issues and favors spending money on walkways.
Answer:
Multiply the probabilities: 0.80 * 0.85 = 0.68
Comments and questions welcome.
More Algebra 2 problems.
No comments:
Post a Comment