Ah, ah, if you are good at math, please help me.
If a/b=c/d, then (a+c)/(b+d)=a/b=c/d? Please prove. Ah ah ah. Please help, I'm really desperate. I fell asleep in math class today. The teacher asked me to solve this problem on a whim. Otherwise, perform in front of the whole class. Before the second class in the afternoon.
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Same as the original poster, I usually fall asleep in math class! When I can solve a problem, the whole class looks at me like I'm a freak. Not being able to solve it is normal...
Because a/b = c/d, therefore a = c, b = d, so a + c = 2a, b + d = 2b. Therefore, (a + c)/(b + d) = 2a/2b = a/b, so it is also = c/d. Therefore, (a + c)/(b + d) = 2a/2b = a/b = c/d. Understand?
Flying was wrong, it should be a\b = c\d, so a = nc, b = nd, so (a + c)\(b + d) = (nc + c)\(nd + d) = (n + 1)c\(n + 1)d = c\d = a\b
Thank you.. I really appreciate it. I am in the third year of junior high, but I'm not good at math.
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