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Algebraic Expressions (Probs really easy solution)

Hello

im trying to simplify algebraic expressions but this part of a question has me stumped

2CT x -T

What does that equal as it has completley thrown me off. if you could also show how you get the answer i would really appreciate it! it just doesnt seem to work following the rules for normal simplification, but then again this is all very new to me!

there is 1 more which is (3y^2+4y-2) - (7y^2-20y+8)

i got -4y^2 -16y +6 however this appears to be completley wrong.

Thanks
Reply 1
For the first one, treat -T as -1xT and then multiply each part separately

For the second, expand the second bracket to include the -ive
Reply 2
Original post by Jordan97
For the first one, treat -T as -1xT and then multiply each part separately

For the second, expand the second bracket to include the -ive


Thanks for your reply

I still dont understand what you would do with the -1 to make it so the answer would be 2CT^2 it seems as though it just cancels out? but that cant be right

and for the second one do you mean doing -1 x everything in the second bracket than putting it back into a bracket? im so confused, is there a name for the rules of this that i can look up? just gotten back into education after 6 years and im struggling with this, most of these types of questions im fine with and i can grasp trig with no real issues but this!

thanks
Reply 3
Original post by nomad992
Thanks for your reply

I still dont understand what you would do with the -1 to make it so the answer would be 2CT^2 it seems as though it just cancels out? but that cant be right

and for the second one do you mean doing -1 x everything in the second bracket than putting it back into a bracket? im so confused, is there a name for the rules of this that i can look up? just gotten back into education after 6 years and im struggling with this, most of these types of questions im fine with and i can grasp trig with no real issues but this!

thanks


The answer is not 2CT^2, this would mean just multiplying by T. If you then multiply this by -1 you get -2CT^2.

And yes. Just multiply everything in the bracket by -1 but there's no need to put it back into a bracket. In fact, the you can also lose the first set of brackets as well
Reply 4
Original post by Jordan97
The answer is not 2CT^2, this would mean just multiplying by T. If you then multiply this by -1 you get -2CT^2.

And yes. Just multiply everything in the bracket by -1 but there's no need to put it back into a bracket. In fact, the you can also lose the first set of brackets as well


Thank you so much! I had asked this question yesterday and someone responded saying it was 2CT^2 then stopped responding so it was utterly lost, thats the answer that i can get!

Thank you very much for your help.
Reply 5
Original post by nomad992
Thank you so much! I had asked this question yesterday and someone responded saying it was 2CT^2 then stopped responding so it was utterly lost, thats the answer that i can get!

Thank you very much for your help.


No worries :smile:

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