Erfana Beevee Binte Hassan Shariff's answer to Ray's Secondary 4 A Maths Singapore question.

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Erfana Beevee Binte Hassan Shariff
Erfana Beevee Binte Hassan Shariff's answer
275 answers (Tutor Details)
Use (a) coordinates of the 2 points to find the gradient of the str line graph first. Then, using x=9, find X. Y is unknown. So (1/3, Y) is another point on the str line graph. Any 2 points on str line graph has same gradient. Take any point in (a) and (1/3, Y), equate to gradient to find Y. Then, find y.