7 / 12 + 5 / 7-7 / 12 + 5 / 7 = simple calculation The process should be detailed

7 / 12 + 5 / 7-7 / 12 + 5 / 7 = simple calculation The process should be detailed

7/12+5/7-7/12+5/7
=7/12-7/12+5/7+5/7
=0+10/7
=10/7

4（a-2b）^2+13a-26b+9
I'm very anxious to do cross multiplication. How can I do this kind of cross multiplication when the coefficient of quadratic term is not one

Minus 2 divided by 1 / 2 =?

Minus 4

If a Quasilinear of hyperbola x ^ 2 / 16-y ^ 2 / b ^ 2 = 1 is tangent to circle x ^ 2 + y ^ 2 + 2x = 0, then the value of B is?

a=4,c²=a²+b²=16+b²
The guide line is x = ± (16 / C)
The equation of a circle can be reduced to (x + 1) &# 178; + Y & # 178; = 1, the center of the circle is (- 1,0), and the radius is r = 1
So the left guide line x = - 16 / C is tangent to the circle, and the distance d from the center of the circle to the guide line is = - 1 + 16 / C = 1,
The solution is C = 8, so B & # 178; = C & # 178; - A & # 178; = 48, B = 4 √ 3

Solving the equation: 5 / 7 x-4 / 3 = 2 and 5 / 12
105%÷x＝10.5

5x/7-4/3=2+5/12
5x/7=45/12
5x/7=15/4
x=21/4
105%÷x＝10.5
1.05/x=10.5
x=1.05/10.5
x=0.1

Let m = {x | - 1 ≤ X

The intersection of two sets is an empty set, which means that the two intervals they represent do not coincide with each other
For n set, we should separate X and K left and right, because they are different variables, n = x, X is less than or equal to K
You try to stroke on the number axis
It can be seen that n set is an interval extending from K to the left, while M set is an interval with limit at both ends
In order to make them not coincide, only K is less than - 1

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 +. + 49 + 50 simple calculation,

Add 1 + 49, 2 + 48. In turn, add 25 and 50 to get 1275

If the symmetric point of point P (- 3,2m + 1) with respect to X is on the angular bisector of the second and fourth quadrant, find the value of M

Suppose the symmetric point is Q (a, b)
1、 Because point Q (a, b) is on the bisector of quadrant two or four, so a = - B, that is, the coordinates of point q are (a, - a);
2、 Because P (- 3,2m + 1) and Q (a, - a) are symmetric about X axis, so - 3 = a, - (2m + 1) = - A
3、 M = - 2

What time is three and two fifths
fast

3:24

The function y = ax & sup2; intersects with the image of the straight line y = 2x-3 at the point (1, b) to find the values of a and B, the opening direction, the axis of symmetry and the vertex coordinates of y = ax & sup2,
Make a sketch of y = ax & sup2

Bring in the coordinates
b=a*1^2=a
b=2-3=-1
∴a=b=-1
Y = ax & sup2; that is y = - x ^ 2
The opening is downward, the axis of symmetry is a straight line, x = 0, and the vertex is (0,0)