If the line L1: y = 2x + 3 and the line L2 and L1 are symmetric with respect to the line y = - x, then the slope of the line L2 is () A. 12B. -12C. 2D. -2

If the line L1: y = 2x + 3 and the line L2 and L1 are symmetric with respect to the line y = - x, then the slope of the line L2 is () A. 12B. -12C. 2D. -2

According to the meaning of the problem, in the L1 equation, replace y with - x, and replace x with - y, then the linear L2 equation of the symmetry of L1 with respect to the linear y = - x is x-2y + 3 = 0, so the slope of the linear L2 is 12, so a

I'd like one and a____ (half) kilos banana

Just fill in the prototype
I want a kilo and a half of bananas. Although kilos is plural, half half half is still the same. In English, more than one kilo is plural, so a kilo and a half is also plural

The parabola y = - x2-2x + m, if its vertex is on the X axis, then M=______ ．

∵ parabola y = - x2-2x + m, if its vertex is on the X axis, ∵ 4 × (− 1) × m − (− 2) 24 × (− 1) = 0, the solution is m = - 1. So the answer is: - 1

Solving mathematical problem 2 to the power of x = 2-x

Let y = 2-x,
The equations are as follows
1.y=2-x
2. X power of y = 2
Draw a picture and find the abscissa of the intersection point

On the hyperbola X & sup2 / 16-y & sup2 / 9 = 1, the distance between the point and the left focus is twice that of the right focus

Let the point be p (x0, Y0). According to the hyperbolic equation: A & sup2; = 16, B & sup2; = 9, so C & sup2; = A & sup2; + B & sup2; = 25, a = 4, B = 3, C = 5, left focus F1 (- 5,0) right focus F2 (5,0) Pf1 = 2pf2 and pf1-pf2 = 2A = 8, so Pf1 = 16, PF2 = 8, eccentricity e = C / a = 5 / 4, left quasilinear x = - A & sup2 / / C = -

Let a, B, x, y satisfy a + B = x + y = 3, ax + by = 7. Find the value of (A2 + B2) XY + AB (x2 + Y2) & nbsp

∵ a + B = x + y = 3, ∵ a + B (x + y) = 9, ∵ ax + by + (ay + BX) = 9, ∵ ax + by = 7, ∵ ay + BX = 2, (A2 + B2) XY + AB (x2 + Y2) = xya2 + xyb2 + abx2 + aby2 = ax (ay + BX) + (by (BX + ay) = (ay + BX) (AX + by), the original formula is 14

F (x) = a quadratic function, f (x) + F (2x) = the square of 5x + 6x + 6
The expression of F (x)

f(x)=ax²+bx+c
f(2x)=4ax²+2bx+c
f(x)+f(2x)=ax²+bx+c+4ax²+2bx+c=5ax²+3bx+2c=5X²+6X+6
5a=5
a=1
3b=6
b=2
2c=6
c=3
f(x)=x²+2x+3

Parabola y = 1 / 2x square + 3x-7 / 2
Coordinates of the intersection point with the x-axis

The ordinate of the intersection with X axis is 0
Substituting y = 0
X²/2+3X-7/2=0
X²+6X-7=0
（X-1）（X+7）=0
X-1=0,X1=1,
X+7=0,X2=-7
The abscissa of the two points are 1, - 7
So the intersection coordinates are (- 7,0), (1,0)

The vertex P of the parabola y = - x square + 4x + n-2 is on the x-axis, and the coordinates of the intersection of the parabola and the two axes_______

Because the vertex P of parabola y = - x squared + 4x + n-2 is on the x-axis, so - X & # 178; + 4x + n-2 = 0 has only one root, so △ = 4 & # 178; - 4 × (- 1) × (n-2) = 0, the solution is n = - 2, so y = - X & # 178; + 4x-4 = - (X-2) &# 178; let y = 0, get x = 2, so the intersection coordinate (2,0) with X-axis makes x = 0, get y = - 4, so with y

A junior one application problem, can solve the speed
The questions are as follows:
In order to keep the total amount of sales unchanged, how much more will the sales volume increase than the original price?
The solution is as follows:
1. Only one unknown x can be set;
2. There should be process and analysis;
3. We can't only get the number;
4. It must be solved before 9:00 today;
5. Hope to write the analysis in detail;
6. I haven't thought of it yet
Add 50 points for the solution

1/9
Suppose the original total sales amount is x, then the actual total sales amount is (1-10%) * x = 0.9x
In order to keep the total amount of sales unchanged, the sales volume should be increased compared with the original price
（X-0.9X）/0.9X=01.X/0.9X=1/9