1.Half a number squared decreased by four to forth is thirty-three.

题目

1.Half a number squared decreased by four to forth is thirty-three.
2.Five times a number increased by five is seventy-five.
3.A number to its square root times double the reciprocal of the number is one forth.
如何用数学式子表达以上题目?（中文翻译也行)

答案

把一个数减掉一半后 再平方 再减4的4次方 得33
把一个数乘以5 再加5 得到75
一个数 开根号 再乘以它的倒数的两倍 得到1/4