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Jamie Lee

Asked 9 years ago

SG Secondary 3 Number and Algebra

Hi Teachers, can you help me to solve qns 2b. My sister has forgotten how to do it. please...

Replies 6

Zhong Shu Hao

inverse proportion of a and b means.... ab=k where k is a constant. So in this case, yx^2=k where k is a constant y=k/x^2 k/(5)^2 - k/(10)^2 = 1.2 3k/100= 1.2 k = 40 Hence, yx^2 = 40. (i) yx^2 = 40 Also, y = 40/x^2 (ii) when x=-2, y=40/(-2)^2 = 40/4 =10.

6 years ago

Jamie Lee

Thanks Teacher.

6 years ago

Zhong Shu Hao

Jamie Lee Do you need part b?

6 years ago

Jamie Lee

yes Zhong Shu Hao

6 years ago

Zhong Shu Hao

6 years ago

Jamie Lee

yes it is clearer now. thanks Zhong Shu Hao

6 years ago

Adrian Ng

Asked 9 years ago

SG Primary 6 Measurement

Making it visual...

Replies 2

Mavis Low

Thanks Adrian! Like what I mentioned in an earlier post, how do you know that the point between P and Y, to the point X, to the point T, actually forms a straight line? And same for the other side? Can it be assumed? Because I think at the secondary school level, info like this should be stated explicitly in the qn, otherwise we cannot assume.

6 years ago

Adrian Ng

The first sentence mentioned that figure is made up of triangles but I feel it can be more specific. By the way, pupils can actually seek clarification.

6 years ago