1.for what positive number is the square root of the number the same as the number divided by 40?2.what is the total number of right angles formed by the edges of a cube?以上两题请帮忙翻译一下,我觉得按我的理解怎么也做不出正

1.for what positive number is the square root of the number the same as the number divided by 40?2.what is the total number of right angles formed by the edges of a cube?以上两题请帮忙翻译一下,我觉得按我的理解怎么也做不出正
1.for what positive number is the square root of the number the same as the number divided by 40?
2.what is the total number of right angles formed by the edges of a cube?
以上两题请帮忙翻译一下,我觉得按我的理解怎么也做不出正确答案
3.the square of x is equal to 4 times the square of y.if x is 1 more than twice y.what is the value of
A.-4
B.-1/2
C.-1/4
D.1/4
E.1/2
我觉得超级诡异,怎么算都是C,

1.for what positive number is the square root of the number the same as the number divided by 40?2.what is the total number of right angles formed by the edges of a cube?以上两题请帮忙翻译一下,我觉得按我的理解怎么也做不出正
嗯 LZ 要出国吧 同仁同仁 !
1.哪个正数的平方根和它被 40 除的商相同?
设这个正数为 x ,则可得 (以下√代表根号,^ 代表平方)
√x = x ÷ 40
两边平方,得
x = x^2 ÷ 1600
∵ x 为正整数,两边同除以 x,得
1 = x ÷ 1600
∴ x = 1600
2.一个正方体的所有棱共组成了多少个直角?
立体几何问题.正方体每个顶点由三条棱相交而形成,故每个顶点处有 3 个直角
又正方体共有 8 个顶点,故一共组成了
3 × 8 = 24 个直角
3.已知 x 的平方等于 y 的平方的 4 倍.如果 x 比两倍的 y 大 1,求 x 值.
依题意,可列出两个方程
x^2 = 4 × y^2 ①
x = 2y + 1 ②
将 ② 代入 ① 得
(2y + 1)^2 = 4 × y^2
左边 = 4y^2 + 4y + 1
∴ 4y^2 + 4y + 1 = 4 × y^2
4y + 1 = 0
y = -1/4 ③
将 ③ 代入 ② 得
x = 2 × (-1/4) + 1 = 1/2
答案选 E.(楼主算的结果应该是 y ,可题目问的是 x 的值)
希望以上的解析能对你有帮助,也希望你的出国旅途一帆风顺!