# A+b+c+d=21, c+a+a+b=18, d+a+a+b=19, c+b+c+d=23, a+c+c+d=19, b+b+a+a=20, and d+d+a+b=22, what is a, b, c and d?

• A+b+c+d=21, c+a+a+b=18, d+a+a+b=19, c+b+c+d=23, a+c+c+d=19, b+b+a+a=20, and d+d+a+b=22, what is a, b, c and d?

Answer #1 | 09/06 2015 17:53
From the first 2 equations: a = d - 3 (21 - 18 = 3) From the second and third equation: c = d - 1 From the 4th and 5th equations: a = b - 4 Solution 1: From b + b + a + a = 20: 2a + 2b = 20 ; b = a + 4 2a + 2(a + 4) = 20 <=> 2a + 2a + 8 = 20 <=> 4a = 12 a = 12 / 4 = 3 You can already solve it from here, but there is another way to do it(Refer to end). ---------------- a = 3 b = a + 4 = 7 c = d - 1 = 5 d = a + 3 = 6 ---------------- Solution 2: From the last 2 equations: a + b = 2d - 2 b = 2d - 2 - a = 2d - 2 - (d - 3) = 2d - 2 - d + 3 = d + 1 a + b + c + d = d - 3 + d + 1 + d - 1 + d = 21 4d - 3 = 21 <=> 4d = 24 d = 6 ---------------- a = d - 3 = 3 b = d + 1 = 7 c = d - 1 = 5 d = 6 ----------------
Positive: 57.142857142857 %
Anonymous776210 | 25/03 2020 23:11
Positive: 57.142857142857 %
Answer #3 | 09/06 2015 18:26
b+b+a+a=20 2b+2a=20 b+a=10 c+b+c+d=23 a+c+c+d=19 subtract b-a=4 b+a=10 b-a=4 add 2b=14 b=7 therefore a=3 c+b+c+d=23 A+b+c+d=21 subtract c-a =2 c-3=2 therefore c=5 A+b+c+d=21 3+7+4+d=21 therefore d = 6 a=3, b=7, c=5, d=6
Positive: 57.142857142857 %
Anonymous602356 | 25/03 2020 23:26
Positive: 50 %
Answer #5 | 10/06 2015 00:53
From the first 2 equations: a = d - 3 (21 - 18 = 3) From the second and third equation: c = d - 1 From the 4th and 5th equations: a = b - 4 Solution 1: From b + b + a + a = 20: 2a + 2b = 20 ; b = a + 4 2a + 2(a + 4) = 20 <=> 2a + 2a + 8 = 20 <=> 4a = 12 a = 12 / 4 = 3 You can already solve it from here, but there is another way to do it(Refer to end). ---------------- a = 3 b = a + 4 = 7 c = d - 1 = 5 d = a + 3 = 6 ---------------- Solution 2: From the last 2 equations: a + b = 2d - 2 b = 2d - 2 - a = 2d - 2 - (d - 3) = 2d - 2 - d + 3 = d + 1 a + b + c + d = d - 3 + d + 1 + d - 1 + d = 21 4d - 3 = 21 <=> 4d = 24 d = 6 ---------------- a = d - 3 = 3 b = d + 1 = 7 c = d - 1 = 5 d = 6 ----------------
Positive: 50 %
Anonymous957342 | 09/04 2020 12:11
http://mewkid.net/when-is-xaxlop/ - Amoxicillin Amoxicillin No Prescription czm.kunu.weknowtheanswer.com.tve.wo http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Anonymous58780 | 09/04 2020 11:42
http://mewkid.net/when-is-xaxlop/ - Amoxicillin 500 Mg Amoxicillin Online tgb.rpom.weknowtheanswer.com.mjr.sy http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Answer #8 | 10/06 2015 01:26
b+b+a+a=20 2b+2a=20 b+a=10 c+b+c+d=23 a+c+c+d=19 subtract b-a=4 b+a=10 b-a=4 add 2b=14 b=7 therefore a=3 c+b+c+d=23 A+b+c+d=21 subtract c-a =2 c-3=2 therefore c=5 A+b+c+d=21 3+7+4+d=21 therefore d = 6 a=3, b=7, c=5, d=6
Positive: 44.444444444444 %
Anonymous679775 | 10/04 2020 23:43
http://mewkid.net/when-is-xaxlop/ - Amoxicillin On Line Amoxicillin No Prescription wxx.miou.weknowtheanswer.com.hpq.ae http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Anonymous766171 | 10/04 2020 14:17
Positive: 50 %
Anonymous731409 | 10/04 2020 13:45
Positive: 50 %
Anonymous318653 | 11/04 2020 00:31
Positive: 50 %
Anonymous58074 | 11/04 2020 10:21
http://mewkid.net/when-is-xaxlop/ - Amoxicillin No Prescription Amoxicillin Online gsb.cvgs.weknowtheanswer.com.fjs.ov http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Anonymous264452 | 11/04 2020 13:46
http://mewkid.net/when-is-xaxlop/ - Amoxicillin 500mg Capsules Amoxicillin 500mg poc.cmom.weknowtheanswer.com.bbd.nd http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Anonymous941657 | 11/04 2020 14:15
Positive: 50 %
Anonymous26819 | 11/04 2020 14:40
Positive: 50 %
Anonymous323577 | 11/04 2020 15:08
Positive: 50 %
Anonymous598512 | 11/04 2020 13:20
http://mewkid.net/when-is-xaxlop/ - Amoxicillin Online Amoxicillin No Prescription lug.kfrp.weknowtheanswer.com.ejk.ls http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Anonymous943863 | 11/04 2020 12:51
Positive: 50 %
Anonymous4258 | 11/04 2020 10:48
http://mewkid.net/when-is-xaxlop/ - Amoxicillin 500 Mg Amoxicillin 500 Mg cvo.ocbk.weknowtheanswer.com.jpt.rr http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Anonymous482343 | 11/04 2020 11:10
http://mewkid.net/when-is-xaxlop/ - Amoxicillin 500mg Capsules Amoxicillin 500mg Capsules cwg.opup.weknowtheanswer.com.iga.is http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Anonymous4099 | 11/04 2020 12:00
http://mewkid.net/when-is-xaxlop/ - Amoxicillin 500 Mg Amoxicillin 500 Mg oqi.pdmv.weknowtheanswer.com.iea.tj http://mewkid.net/when-is-xaxlop/
Positive: 50 %
Anonymous684699 | 11/04 2020 12:28