Since the discriminant is positive, this means we have two distinct real solutions.
If a, b, and c are rational numbers, then a discriminant of D = 40 indicates the two solutions are not rational. We would need D to be a perfect square to get two rational solutions.
Answer: 
Step-by-step explanation:
We see that g(x) is a straight line that passes through the origin, just like f(x), so g(x)=kx for some constant k.
Since g(x) passes through (4,2), we know that 2=4k, and thus k=1/2.
So, 
Answer:
Judy is 16 years old
Step-by-step explanation:
J = Judy's age
A = Adams age
J = 2A
Six years ago (subtract 6 from the ages)
(J-6) = 5*(A-6)
Distribute
J-6 = 5A - 30
Substitute J = 2A
2A -6 = 5A -30
Subtract 2A from both sides
2A-2A -6 = 5A-2A -30
-6 = 3A -30
Add 30 to each side
-6+30 = 3A-30+30
24 = 3A
Divide by 3
24/3 = 3A/3
8 = A
Adam is 8 years old now
We need to find Judy's age
J = 2A
J = 2*8
J = 16
Judy is 16 years old
1.42 because you subtract 10 from the price
