SOLUTION: a=1/2b-4 Which of the following statements is true for this formulas? a.When the value of b is less than 8, a is negative b.When the value of b is greater than 8, a is negative?

Algebra ->  Distributive-associative-commutative-properties -> SOLUTION: a=1/2b-4 Which of the following statements is true for this formulas? a.When the value of b is less than 8, a is negative b.When the value of b is greater than 8, a is negative?      Log On


   

Question 73414: a=1/2b-4
Which of the following statements is true for this formulas?
a.When the value of b is less than 8, a is negative
b.When the value of b is greater than 8, a is negative?
c.When the value of b is less than 8, a is positive.
d.When the value of b is greater than 4, a is positive.
Thanks!
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
If we let b=8 then
a=%281%2F2%29b-4
a=%281%2F2%29%288%29-4
a=4-4
a=0
If we chose a number less than 8 (say 6) then
a=%281%2F2%29%286%29-4
a=3-4
a=-1
So if b is less than 8 then a is negative (choice a)
If you are unsure, you can graph by letting a=y and b=x and you'll see which portions are positive and negative.