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Algebra - Are my answers right to these questions?

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OP listen to the others. I only replied because no one else was, but others are now.
No, 1d should be -8x not +2x and 4a should be +2 not +3..
1d, 4a, 4b and 4c are incorrect.
for 1d, check your signs
for 4a, i think you've added something up incorrectly
for 4b, you got to w^2 - 3w - 3w + 9, which is correct, but you collected your terms incorrectly.
for 4c, check your signs
and for 5 in general, you don't need the 1 in front of x, e.g. 1x is written as x
Original post by Stevo F
And retry 1d and 4a


Original post by 4Kaylum
1d incorrect - check your pluses and minuses again: `-3x + 2y - 5x + 7y`.

4a, 4b, and 4c are also incorrect, so I recommend you work on your multiplying out brackets. I recommend using a grid for it - I'll attach an image of what I mean (if I work out how to, I literally just made an account).
Sketch.png

All of 2 and 5 look correct, though, so you're doing pretty well on that front c:


Original post by justinawe
1(d), 4(a), 4(b), 4(c) are incorrect




Are the answers: 1d) 8x+9y 4a) y2 + 3y + 2 4b) w2 + 6w + 9 4c) 7p - 1
Reply 24
Avatar for 4Kaylum
4Kaylum
1
Original post by Maths_English
Are the answers: 1d) 8x+9y 4a) y2 + 3y + 2 4b) w2 + 6w + 9 4c) 7p - 1


1d is wrong again - right numbers but wrong signs.
4a is right, 4b needs the signs checking but you have the right numbers, and you need to check over how you did 4c again (you're getting there but you've not quite got it yet).
Original post by 4Kaylum
1d is wrong again - right numbers but wrong signs.
4a is right, 4b needs the signs checking but you have the right numbers, and you need to check over how you did 4c again (you're getting there but you've not quite got it yet).


1 d) -8x + 9y
4 b) w2 - 6w + 2
4 c) This is how I did it

(2p + 1) (3p - 1)
6p - 2p + 3p - 1
6p - 2p = 4p 4p + 3p = 7p
7p - 1
Reply 26
Avatar for 4Kaylum
4Kaylum
1
Correct and correct for 1d and 4b!

4c is missing a squared when you multiply `2p` and `3p`.
Original post by 4Kaylum
Correct and correct for 1d and 4b!

4c is missing a squared when you multiply `2p` and `3p`.


Ah I see because both contain p

6p2 + 1p - 1
Reply 28
Avatar for 4Kaylum
4Kaylum
1
Original post by Maths_English

6p2 + 1p - 1


Yeah, there you go!
Original post by 4Kaylum
Yeah, there you go!


So with the answers now corrected, is everything right?
Reply 30
Avatar for Rauhan
Rauhan
9
Original post by Maths_English


1) a) 3a b) 8d c) 6x+2y d) 2x+9y
2) a) d5 b) 16ef c) g9 d) h7
3) a) 2a + 6 b) 6u - 15 c) 3x2 + 2x d) 4b2 -6b
4) a) y2 + 3y + 3 b) 6w4 - 9 c) 6p2 - 5p - 1 d) q2 - 1
5) a) 2(2 - 5x) b) 2(3x + 1y) c) -4(1x + 2) d) 2a(5 + 4a) e) 3b(3b - 1c)


Answer for 4a is (y^2 +3y+2)
4b : w^2-6w+9
4c: 6p^2+p-1

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