You only get to ask two questions. So the others were deleted:
1. What is the formula for the determinant of a 3 x 3 matrix ?
= aei + bfg + cdh - ceg - bdi - afh
2. Solve the inequality |2x − 4| < 10. Write the solution in interval notation and graph it:
To remove absolute value bars with < or <, write
-10 < 2x - 4 < 10, and solve for x in the middle:
Add 4 to all three sides +4 +4 +4
------------------
-6 < 2x < 14
Divide all three sides by 2 -3 < x < 7
Here is the graph:
-----------o=============================o------------
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11
Here is the interval notation, which is an abbreviation for the graph:
(-3,7)
Edwin