Which of these statements isn't always true? A. a + (-b) = - b + a B. a - (-b) = (-b) - a C. (a+b) + (-c) + a + b [b + (-c) ] D. - (a) = a

What is the difference between 20 and - 60

What is the slope of (18,-5) (18,20

What is the greatest composite odd numbers less than 40

Solve the system of equations by substitution. x+y=18 y=8x

1+3+5+7 + ... + 997

Describe a real life sittuation that can be modeled by the equation 2x plus 5 equals 10

How many 9 inch ribbons can be cut from 1 1/2 yards of ribbon?

The value of the cumulative standardized normal distribution at z is 0.8770. the value of z is

Sally's grocery store is selling eggs for $1.56 a dozen. what is the unit price per egg

Write an expression for the total cost of each hotel if n represents the number of nights he will stay. Holiday Inn:$80 a night plus $10 for parking Days Inn:$110 a night with a $50-off coupon