请教一道Prep数学题

afflare

[attachimg]63137[/attachimg]

题目如上图，那位NN告诉我这题什么意思啊？

afflare

the answer is 5 for this question.

monacopig

4+z=m, e+y=n =>m+n=14+y
f+y=-4, 4+y=-5=>f=5=>y=-9

so, m+n=5

afflare

原来如此！Thanks LS!