SOLUTION: 2 3 4 15 12 3 4 5 28 20 4 5 6 X 30 5 6 7 66 42 6 7 8 91 56 Find X

Algebra ->  Matrices-and-determiminant -> SOLUTION: 2 3 4 15 12 3 4 5 28 20 4 5 6 X 30 5 6 7 66 42 6 7 8 91 56 Find X      Log On


   

Question 469166: 2 3 4 15 12
3 4 5 28 20
4 5 6 X 30
5 6 7 66 42
6 7 8 91 56
Find X
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
X=45
From the first line 2 3 4 15 12
12=3*4
15=(2*3)*2+3
From the second line 3 4 5 28 20
20=4*5
28=(3*4)*2+4
From the fourth line 5 6 7 66 42
42=6*7
66=(5*6)*2+6
From the fifth line 6 7 8 91 56
56=7*8
91=(6*7)*2+7
Then from the third line 4 5 6 X 30
X=(4*5)*2+5=45