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Mrs Tibble’s Year 10240 comments to Mrs Tibble’s Year 10 |
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Sorry Mrs Tibble I still cant do question 10 or 7
but 7a i dont get
Hi Alice and Jasmine,
Q7 Work out how long it takes her to do the first bit of her journey:
her speed is 15mph so if she went 15 miles it would take her an hour.
She is only going 5 miles so how long will this take?
Last bit of journey takes 10 min so add the 2 times together.
Mrs T
Hi, which page and exercise is it because the one i have doesn’t have C or anything to do with the subject.
Hi Catherine,
Sorry for delay – parents’ evening.
Page 112 Ex 23C
JT
Hi Mrs Tibble, i have started the hw, and i just checked the first answer. But it is wrong :’( shall i write up what i got?
Thank you
Hi Charlotte,
Is this exercise 5J?
In 1 and 2 and 4, subtract the equations; in Q3 add them. You shouldn’t have any problems with 5J because the y terms match in every case.
Mrs T
yeah it is, I didn’t seem to have any problems while doing it but the answer I got was 17 :/
and i die.. in question 1 in 5j does x = 3?
OMG it does!
oooooo don’t worry, something just clicked
Light bulb moments seem to be happening
Well done!
What do I do when the signs dont match? like + and -
Add the equations.
Mrs Tibble, for 5k is x 17/11?
Hi Charlotte,
No, the answers in both exercises are integers. When you doubled the 2nd equation, you only doubled one side of it.
Mrs T
mrs tibble i need help! the answer i got for ex 5j q1 for y was -2.67 and i think i’ve done something wrong aah
Mrs Tibbs! i need help on q4 ex5J.. my sister worked it out i think but in a confusing way i don’t understand. helppp.
Mrs Tibble i’m trying to use the method you showed me but i don’t understand.
Hi Alice,
What did you get for x?
Mrs T
Catherine,
Do the method in your notes then for 5J. The y terms are the same in every equation so subtract when the y terms have the same sign, and add when they have opposite signs.
Mrs T
India,
Do what I’ve just told Catherine to do.
Mrs T
I don’t know what to divide by
Hi Catherine,
In 5J you don’t need to do any dividing. The y terms are both the same each time so just get the y terms only on the left and then equate them
eg in Q1 y=17-5x and y=11-3x
Since they are both equal to y, they must be equal to each other. No fractions in this exercise.
JT
Never mind it appears I’ve read 5L instead of 5j :S I can be so stupid sometimes
lol
um i can’t do excersize 5k i’m giving up :p
Alice,
Q1 and Q4 If you double everything in the second equation it will be the same as ex 5J.
Q2 x2nd equation by 3
These all make the y’s match
Q3 multiply 1st equation by 3 then the x’s will match.
Mrs T
Hello Mrs Tibble I am getting a bit confused on questions 13 on wards :/
Hi Jasmine,
I don’t have a book here so could you type out a couple of the questions please?
JT
Question 15:
xsquared – 7x + 8 = 0
and I have already worked out that the brackets start like this:
(x- ) (x- )
Hi Jasmine,
Are you sure that it says +8?
It would need to be -8 to work.
For x^2 – 7x – 8 = 0
you would get
(x – 8)(x + 1) =0
because -8 x 1 = -8 for the end
and -8 + 1 = -7 for the middle.
If it says +8, it’s wrong!!
Ahhhhh!! that would explain my confusion, thank you!
and it definitely says +8 in the book
Hi mrs tibble, i am trying to do the home work, but both of my answers are wrong and i dont know where i am going worng :’( shall i put what i am dong?
charlotte
thank you
Yes please.
How do you know your answers are wrong?
From answer book:
Q2. -0.29, -1.71
Q5. -0.57, -1.77
Q8. 2.16, -4.16
2X squared + 4x + 1=0
a=2
b=4
c=1
x=-b +/- (square root) b squared – 4ac
————————————–
6
x=-4 +/- (square root) 16-4 X 2 X 1
———————————–
6
x=-4 +/- (square root) 24
—————————
6
but you cant square root 24..
Hi Charlotte,
First mistake is in line 1
denominator is 2a which is 4 not 6
Second mistake is in line 3:
16 – 8 isn’t 24
Also, when you do the square-rooting, don’t expect nice numbers. That’s why it says give your answers correct to 2dp.
Good luck!
ooo right ok thank you! i will give it another go now