Lower Secondary Mathematics

PSLE marks the graduation of Primary school students and their entry into Secondary schools as teenagers. Discuss all issues about Secondary schooling here.

Re: Lower Secondary Mathematics

cftan wrote:A man travels from town A to town B at an average speed of 4km/h and from town B to town A at an average speed of 6km/h. If he takes 45minutes to complete the entire journey, find his total distance travelled.

Distance = Speed x Time.
Time from A to B = Distance/4
Time from B to A = Distance/6

Total time = Distance/4 + Distance/6 = Distance (1/4 + 1/6) = 3/4 hr.

You can then work out the total Distance = Distance x 2.

iwork
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Re: Lower Secondary Mathematics

Sruthi
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Re: Lower Secondary Mathematics

Sruthi
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Re: Lower Secondary Mathematics

Jmaths.SG
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Re: Lower Secondary Mathematics

Can anyone help me with this question.

1. The sine of an angle is 0.7420. Give two possible values for the angle in degrees.

questionable_i
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Re: Lower Secondary Mathematics

questionable_i wrote:Can anyone help me with this question.

1. The sine of an angle is 0.7420. Give two possible values for the angle in degrees.

sin (angle) = positive, when 0 < angle < 180
sin (angle) = negative, when 180 < angle < 360

Since sin (angle) = 0.7420 -> positive
Both angles must be between 0 to 180.
sin^(-1) 0.7420 = 47.9 deg (first ans)
180 deg - 47.9 deg = 132.1 deg (second ans)

Jmaths.SG
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Re: Lower Secondary Mathematics

Kindly help with the following qn, thanks.

Without drawing the graphs, explain why the simultaneous equations
y = -2x + 5
y = 2x - 33
have no solution

tankee

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Re: Lower Secondary Mathematics

tankee wrote:Kindly help with the following qn, thanks.
Without drawing the graphs, explain why the simultaneous equations
y = -2x + 5
y = 2x - 33
have no solution

Hi, is there any typo error in the question?

I am able to find the solution, which is x= 9.5 and y=-14.

If the question was to solve

y = 2x + 5
y = 2x - 33
or
y = -2x + 5
y = -2x - 33

then there is no solution

working:
sub. y = 2x+5 into the second equation,
2x+5=2x-33
5=-33 （Not a valid equation)
so no solution.

Please us know if you need further help, the tutors in our centre (who are IP/GEP/RGS/NYGH/ACJC teachers) are able to help you.

GreenBelt

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Re: Lower Secondary Mathematics

Need help with the following questions:-

1) 10f2 - 15f = 0

17g + 45
2) g2 + ----------- = 5
2

Not sure how to place the superscript of square thus f2 and g2.

Question 2 is truncated.

Anyone can tell me how to upload the in pic? Cos has reduced size many times and change from bmp to jpg and etc still cant post.....

Sharmum
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Re: Lower Secondary Mathematics

tankee wrote:Kindly help with the following qn, thanks.
Without drawing the graphs, explain why the simultaneous equations
y = -2x + 5
y = 2x - 33
have no solution

Hi, is there any typo error in the question?

I am able to find the solution, which is x= 9.5 and y=-14.

......

likewise. But since it has been a while, I thought better seek help to be sure just in case it isn't a typo.

thanks.

tankee