Grades in three tests in College Algebra are 87,59 and 73. The average after final is 75 To calculate:The points needed on the final to average the points to 75.

To write a function f describing cost of sealable books.
The printing and binding cost for a college algebra book is $\mathrm{\$}10$.The editorial cost is $\mathrm{\$}200,000$. The first 2500 books are free.

To calculate: The probability that the selected student of 17-26 age group has received an "A" in the course.
Given Information:
A table depicting the grade distribution for a college algebra class based on age and grade.

Need to find a variable.
$ax+by=cx+z$
solve for x

Self-Check A student scores 82,96,91, and 92 on four college algebra exams.What score is needed on a fifth exam for the student to earn an average grade of 90?

Sometimes when solving very sparse equation systems
$Ax=b$
with conjugate gradient using computers, if A is a very sparse matrix, it can be difficult to utilize the hardware computational power maximally
Does there exist some way to rewrite
$Ax=b\text{ or }{A}^{T}Ax=A^{T}b$
to be able to utilize hardware better?
One idea I had is that often $A^2,A^3$ et.c. are increasingly non-sparse. Maybe it would be possible to take multiple steps at once..?
One motivation why this should be possible is that the Krylov subspaces which the Conjugate Gradient investigates are precisely the powers of the matrix. A second motivation why this is possible is of course Caley Hamilton theorem
$P(A)=0\Rightarrow A^{-1}=P_2(A)$
For some polynomial $P_2$ other than P.

Express $\cos ({\sin }^{-1}x-co{s}^{-1}y)$ as an algebraic expression in x and y.

Twenty-six students in a college algebra class took a final exam on which the passing score was 70. The mean score of those who passed was 78, and the mean score of those who failed was 26. The mean of all scores was 72.
How many students failed the exam?