Is x not equal to 0 in 1 / X-1? Judge and explain the reason Quick answers are highly rewarded!

The denominator is not equal to 0. Your problem is 1 / X-1, not 1 / (x-1), so x is not equal to 0

It is known that 5 times of X is equal to 3 times of Y. is x proportional to y

5x=3y
x:y=3/5
So it's a positive ratio

As shown in the figure, do you remember how to make an angle equal to a known angle with a ruler? Can you explain the reason?
Xiao Ming reviewed the process of drawing and thought as follows: OC = o'c ', OD = o'd', CD = c'd '- △ OCD ≌ △ o'c'd' - angle doc = angle d'o'c '. Can you explain the reason for each step?

Arbitrarily connect two points on the angle to form a triangle, and then use a compass to make three lines equal to the original respectively to form a triangle, that is, congruent with the original. The judging method is SSS, and the corresponding angles are equal
Supplement: Compass intercept, resulting in OC = o'c ', OD = o'd', CD = c'd ', so SSS, two triangles are congruent, so the corresponding angles are equal

If Z, y and Z satisfy x + y = 5 and Z2 = XY + Y-9, then x + 2Y + 3Z=______ ．

∵ x + y = 5, Z2 = XY + Y-9, ∵ x = 5-y, substituting Z2 = XY + Y-9, Z2 + (Y-3) 2 = 0, z = 0, Y-3 = 0, ∵ y = 3, x = 5-3 = 2, x + 2Y + 3Z = 2 + 2 × 3 + 3 × 0 = 8, so the answer is 8

There are 54 students in class 61. The number of girls is four fifths of that of boys. How many boys and girls are there

If x is set for boys and 4 / 5x for girls, then x + 4 / 5x = 54. There are 30 boys and 24 girls

1. If x + y = 6, xy = 3, then the value of XY ^ 2 + x ^ 2Y is 2. If x ^ 2 + y = 3, x ^ 4 + x ^ 2Y = 27, then x= .

xy^2+x^2y
=xy(x+y)
=3×6
=18
x^4+x^2y=27
x²(x²+y)=27
3x²=27
x²=9
｜ x = 3 or - 3

There are 30-40 students in class 61. If the male students are 80% of the female students, there are () students in this class

The ratio of boys to girls is 80:100 = 4:5
The number of students in the class is divided into 4 + 5 = 9 on average, and 36
So there are 36 students in the class

How many square roots does any rational number have?

Negative numbers have no square root
A positive number has two square roots
0 has a square root

There are three numbers a, B and C, the sum of which is 180. The number a is three times the number B, and the number B is two times the number C. what are the numbers a, B and C?

The number a is the number C: 3 × 2 = 6; from the sum multiple formula, we can get: the number C: 180 ÷ (6 + 2 + 1) = 20; the number A: 20 × 6 = 120; the number B: 20 × 2 = 40. Answer: the numbers a, B and C are 120, 40 and 20 respectively

If - (a-5) is negative, the relationship between a-5 and 0 is: a-5____ zero

Because - (a-5) and a-5 are opposite numbers, because - (a-5) is negative, so its opposite number a-5 is positive, so a-5 > 0

Is x not equal to 0 in 1 / X-1? Judge and explain the reason Quick answers are highly rewarded!