Joan's test grade was 84. The class average was 72 and the standard deviation was 4.5. What statement best describes her z-score and her test grade?

Find the domain of the composite function f?g. Write the domain in interval notation.f(x) = , g(x) = x + 4

A. (-?, -12) ? (-12, ?) B. (-?, ?) C. (-?, -8) ? (-8, -4) ? (-4, ?) D. (-?, -8) ? (-8, ?)

Write the system of linear equations represented by the augmented matrix. Use x, y, z, and, if necessary, w for the variables. Then use back-substitution to find the solution.

A. {(, -8, 4)}
B. {(, -6, 4)}
C. {(- 3, - , 3)}
D. {(- , -6, 4)}

Solve the system of linear equations.

A. (-5, 0, -2) B. (-5, -2, 0) C. (0, -2, -5) D. no solution

Add or subtract as indicated. Express the answer as a single polynomial in standard form.(5x2 - 19x + 9) - (2x2 + 15x + 14)

A. 3x2 - 34x + 23 B. 3x2 - 34x + 5 C. 3x2 - 34x - 5 D. 3x2 - 17x + 23