Select all expressions that equal -7 - (-12)
a. 7 + (-12)
b. -7 + (-12)
c. -7 + 12
d. 7 + 12

Ateacher has $80 to buy workbooks. each work book cost $3. if she buys as many workbooks as possible, how much money does she have leftover? a) $2 b) $4 c) $6 d) $8

The hawaiian alphabet has 12 letters. how many permutations are posible for each number of letters?

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. x^2 - 4x - 5 = 0