Q must be positive in F.
F. r squared will be positive, because any number times itself is positive, and to get a positive number for the answer, the two numbers you multiply need to be the same sign. If r squared is positive, q must be too.
G. q does not have to be positive. If r is a negative number, then q can be negative. Say q=-2 and r=-3. -2-(-3) changes to -2+3, which equals 1.
H. Again, q can be negative if r is negative (two negative numbers multiplied together equals a positive answer.
J. q can be negative because even a negative number turns positive when squared.
Hope this helped you. :)
6000*10%=600
600 people voted at at aged 18 to 29 years old.
ANSWER
x coordinates of the intersection points
EXPLANATION
The given system of equations is:


We want to use the graph of these functions to solve

The point of the intersection of the graph gives the solution to the simultaneous equation above.
Hence the x-coordinates of the intersection points gives the solution set of

The last choice is correct.
1.7a + 0.3a = 0.8;
(1.7 + 0.3)a = 0.8;
2 x a = 0.8;
a = 0.8 ÷2;
a = 0.4;