Lol Puneet, go tell that kid!I do not agree with your solutions for question 12 c and 15cii.
for question 12c:
the question states that kim's annual salary in the FIRST year is $30 000 and increases by 5% each SUBSEQUENT year and similarly for alex his annual salary in the FIRST year is $33000 and increase by $1500 each SUBSEQUENT year therefore KIM'S real salary in the 10th year is
30000(1.05)^9 since in the 1st year there is no income rise in the second year there is a rise in income of 1.05* that of the previous year and so on until the nth year where there will be an income of 30000(1.05)^(n-1). Therefore similarly for Alex his salary in the 10th year would be
For question 15 cii)
the answer should be m<-2 and m>2 since this means there is one intercept on the left branch but no intercept on the right (- branch)but also m=2/3
the greater the abs(value for m) the steeper the curve. Also ur solution of m being between -2 and 2 only and not outside these limits is incorrect since if you sub in m=-6 then you only have 1 real solution therefore m<-2 also m is not between these two values since if you sub in m=0 then of course you will have two solutions.
Also for question 16a)
an alternative approach is equating 4x-3 with 5(the gradient of the line) to find the x intercept where the line is a tangent and then solving for c.