前三道.是在看不懂.翻译和解答.谢谢了four times the square of a number is21 more than eight times the number .what is the number?

问题描述:

前三道.是在看不懂.翻译和解答.谢谢了four times the square of a number is21 more than eight times the number .what is the number?

4x的平方=21+8x
(2x+3)(2x-7)=0
x=7/2 或 x=-3/2

4x*x-8x=21
x=7/2
or
x=-3/2

four times the square of a number is21 more than eight times the number .what is the number?
(一个数字的二次方乘以4) 是 (该数字的8倍 +21 )
该数字是?

数字21,8点这个数字是多少

依据题意,有以下式子:设一个数为X,4*X^2=21;4*X^2>8*X;接下来,自己也尝试去动动手吧…^-^英汉词汇:time既有时间的意思,也可以当做次数来说,在作为次数时,是可数名,同时,也有倍数的意思,只要把这个弄清楚了这道题...