Ans me please

Question

()  +    () =8

+       +

()    -   () =6

13        8

Answer 1

Try letting the blanks be the variables w, x, y, z starting from the upper left and working our way clockwise.  Then we have equations y - z = 6,    x + z = 8 and equations w + x=8,    w+y = 13.  Adding the first pair of equations and subtracting the second we get x + y = 14, and x - y = -5.  Adding these two equations we get,

2x = 9

x = 4.5.

Back substituting we get,

y = 9.5

z = 3.5

w = 3.5.

 

Answer 2

Ah, you didn't try yet, did you? I found it in under ten seconds because it wasn't as complicated as it could have been. Simply start by plugging a number into the top left position. Then, subtract it from 8 to get the top right. Subtract each of them from the bottom number to get the middle values. The method is very mechanical, in that it requires no creativity. If you pick an easy number for the top left, your answer will appear very soon...