If x is an integer variable, the mathematical relation cannot be expressed correctly: 5

If x is an integer variable, the mathematical relation cannot be expressed correctly: 5

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If x is an integer variable, the mathematical relation 5 cannot be expressed correctly

A

How to convert the next meter into kilogram
This is about conversion in textile fabrics

1. Gram weight 310 means that the weight per square meter is 310 grams;
2. It is 144 cm wide and 1.44 square meters per 1 meter (100 cm) long;
3. The weight per meter is: 310 * 1.44/1000 = 0.4464 kg (kg) / m;
4. The length of each kilogram is 1 / 0.4464 = 2.24m;
5. The formula of kilogram for meter: length (meter) = total weight (kilogram) * 2.24

Three equilateral triangles of the same size form a trapezoid. How to divide the trapezoid into four trapezoids?
This problem is one of the test questions of grade 4 of Hebei Education Press, which is arranged in the trapezoidal chapter

The bottom of the trapezoid should be connected by the sides of the two triangles. Take the midpoint of each side of the two triangles to make parallel lines of the two waists of the trapezoid, and then intersect with the other two sides of the triangle to connect the intersection

How to make axisymmetric figure

Extend the points on the graph to the other side of the symmetry axis. The extension line should be perpendicular to the symmetry axis, so that the distance between the two symmetry points and the symmetry axis is equal. Then connect the symmetry points, which is the symmetry graph of the original graph

If 5x equals 3Y, is x inversely proportional to y

That is, x = 3Y / 5, x = 3 / 5Y, so the bigger x is, the bigger y is, so it is proportional. If x is bigger and Y is smaller, it is inversely proportional. Do you understand?

If the nonzero vectors AB and CD are parallel, then a, B, C and D are collinear?

No, for example, two vectors on two parallel but not collinear lines, two vectors are parallel but not collinear

As shown in the figure, in RT △ ABC, ∠ ACB = 90 °, AC = BC, D is the midpoint on the edge of BC, CE ⊥ ad at point E, BF ∥ AC intersects the extension line of CE at point F

It is proved that in ∵ RT △ ABC, ∵ ACB = 90 ° AC = BC, ∵ BF ∥ AC, ∵ ACB = CBF = 90 ° CE ⊥ ad, ∵ 2 + 3 = 90 ° AC = BC, ∵ BF = AC, ≌ CBF, ? BF = CD, ? D is B

It is known that f (x) is an odd function defined on (- 1,1) and a decreasing function on (- 1,1) if f (1-A) + F (3a-2) is satisfied

f(1-a)1-a>2-3a>-1
1>1-a,a>0
1-a>2-3a,a>1/2
2-3a>-1,a

It is known that a, B, C and D are not coplanar, and m and N are the barycenters of △ abd and △ BCD respectively

It is proved that: as shown in the figure, connect BM and BN, and extend AD and DC to P and Q respectively, connect PQ, Mn, ∵ m, n to be the center of gravity of △ abd and △ BCD respectively, ∵ P, Q to be the midpoint of AD and DC respectively, and bmmp = bnnq = 2, ∥ Mn ∥ PQ, and Mn is not included in plane ACD, PQ ⊂ plane ACD, ∥ Mn ∥ plane ACD