Nalin Sharma's answer to Chelsea's Secondary 4 A Maths Singapore question.

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Nalin Sharma
Nalin Sharma's answer
35 answers (Tutor Details)
1st
Handwriting and graphs are a bit messy in the last part but the gist of it is that the positive line above the x axis should intersect the graph at 4 points, since the part above the x axis is shorter than the part below, kinda making it the "limiting reagent" deciding the solution to this question.

Also, in the second graph for the last part, the line -0.5 passes over the original graph without intersecting, in case that wasn't clear there. :)
Nalin Sharma
Nalin Sharma
4 years ago
Passes over without intersecting in the end* - allowing for 8 solutions and not 9.
Eric Nicholas K
Eric Nicholas K
4 years ago
Perhaps a snapshot from Desmos online graphing calculator would be good for explanation purposes
Nalin Sharma
Nalin Sharma
4 years ago
Yes definitely, that would probably be more helpful than some 2 min doodles for sure. I'll upload some later in the night if noone has done so yet.