please help with q: 17c, 18 a and 19th .jazakallahkhair.
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Mathematics: Post your doubts here!
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please help with q: 17c, 18 a and 19th .jazakallahkhair.
please help with q: 17c, 18 a and 19th .jazakallahkhair.
17 c- The equations given are 5x=4y+10 and 2y=kx-4 are equal. The first equation is not in standard form, so let's change that equation into standard form in terms of y.
Now the equation is 4y=5x-10.
Second equation is 2y=kx-4.
If two lines are parallel, the gradient or slopes of the two lines will be equal. In this question 1st equation is in 4y but 2nd equation is in 2y. We need to find the value of 'k', so let's keep 2nd equation as it is and we can change the 1st equation's 4y into 2y. To do that we have to divide the 1st equation throughout by 2.
Divide 1st equation by 2=> 2y=2.5x-5
Second equation is 2y=kx-4.
So now we can clearly see the gradient of the 1st line is 2.5, as the two lines equal the gradient will be same so the value of 'k' is 2.5.
18 a) f(x)= (x+2)^3-5.
g[f(x)]= 2[(x+2)^3-5]+10
= 2(x+2)^3-10+10 , the final answer is
= 2(x+2)^3
19 a) A matrix has no inverse if the determinant is equal to 0, because no number can be divided by zero.
In this question the matrix has no inverse. The formula for finding inverse of a matrix is
1*2x-7-0*0 will be equal to 0.
2x-7=0
2x=7
x=7/2
x=3.5
19 b) In identity matrix where x^2-8 , there will be 1. So
x^2-8=1
x^2=9
x=square root of 9
x=+3 or -3
19 c) In this question the matrix is in form
(1 0)
(0 k)
k is the stretch factor
so x-2 = 3
x=3+2
x=5
6 a) To find PQ, we need the length of PB and BQ to apply pythagoras' theorem.
PB=1/2(AB), PB=4, and BQ=4.
PQ is hypotenuse. PQ= square root of (PB^2+BQ^2)
PQ= square root of (4^2+4^2)
PQ=5.65685
adjusted into 3 sig.fig PQ=5.66
6 b) Now we know one length of square PQRS.
Formula for finding area of a square is l^2.
A=5.66^2
A=32.0 (adjusted to 3 sig.fig)
Hello !! I have a 2 sequence questions !
1) I need to find the formula of both
20,17,13,8
7,5,3,1
plz answer asap
Formula for the first sequence is -0.5n(n+3)+22
Formula for the second sequence is -2n+9
First sequence may look little difficult, but the second sequence is very easy.
15 a) OA=a and OB=b, means 6 units are equal to 'a' and 'b' so one unit will be equal to 1/6.
C has position vector 1/3a + 2/3b.
It will be easy if we change the denominators in to 6.
To do that multiply numerators and denominators by 2. So it comes
2/6a + 4/6b.
Here position vector of C is vector OC.
From O, count 2 units towards A (that is 2/6a), then count 4 units right (that is 4/6b) and mark the point C on the diagram.
Hope this will help, if you have any doubt, let me know.
THNKS A LOT!!!!!!.....
you're welcome, please like my message if you like it.
do you need the answers of 15 b & 15 c.
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Please I need help on a few questions from past papers. I am homeschooling so I have nobody to help out.
I will post my first one here from past paper, IGCSE 0581/ paper 21/ oct.nov 2009.
It is question 21, I got part (a) fine but not (b). The answer sheet says 960 but I came to 810.
I did it using Pythagorean theorem; I said 1/2 x 36 x 45.
Thank you to all in advance...
I will post my first one here from past paper, IGCSE 0581/ paper 21/ oct.nov 2009.
It is question 21, I got part (a) fine but not (b). The answer sheet says 960 but I came to 810.
I did it using Pythagorean theorem; I said 1/2 x 36 x 45.
Thank you to all in advance...
(1/2 x 60 x 36) - (1/2 x 12 x 15) - (1/2 x 12 x 5). No need to use pythagoras' theorem.
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Thank you so much but where are you getting those numbers from :$ ? The distance travelled is normally under the line right? I understand the 12 by 15, cos it was slower than the truck but where is the 60 coming from? I got 36 by 45. And also why are you subtracting the outside triangle, the 12 x 5?
If I don't use pythagora's theorem, what else can I use? Sorry, LOL I am a bit slow
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Thank you so much but where are you getting those numbers from :$ ? The distance travelled is normally under the line right? I understand the 12 by 15, cos it was slower than the truck but where is the 60 coming from? I got 36 by 45. And also why are you subtracting the outside triangle, the 12 x 5?
If I don't use pythagora's theorem, what else can I use? Sorry, LOL I am a bit slow
It is a speed-time graph and NOT a distance-time graph. Here the distance traveled is equal to the area under the line or the shape.
One easy method is, first find the whole distance traveled by the car. Then subtract the distances where the car is slower than truck, i.e. where the truck is faster than the car.
Do you need more explanation.
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If you appreciate my help, then please like it.Ah ok, nope I understand it now. Thanks I really appreciated your help
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A square wall is covered with tiles.there are 85 tiles altogether along the two diagonals . How many tiles are there on the whole wall?
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Need urgent help in inequalities !
0580/42/M/J/12 Question no. 3 a to b and c (2)
Thank in advance
0580/42/M/J/12 Question no. 3 a to b and c (2)
Thank in advance
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can someone pls tell me how to solve Q "12 EITHER" in this add maths paper, asap. Would really appreciate...
http://papers.xtremepapers.com/CIE/...matics - Additional (0606)/0606_s12_qp_12.pdf
http://papers.xtremepapers.com/CIE/...matics - Additional (0606)/0606_s12_qp_12.pdf