Let a = 2x-3x. B = x + 4Y. When x = 1. Y = - 2, find the value of 3a-2b It is known that a = 2x-3y. B = x + 4Y. When x = 1. Y = - 2. Find the value of 3a-2b

Let a = 2x-3x. B = x + 4Y. When x = 1. Y = - 2, find the value of 3a-2b It is known that a = 2x-3y. B = x + 4Y. When x = 1. Y = - 2. Find the value of 3a-2b

A = 2x-3y. B = x + 4Y. When x = 1. Y = - 2,
3a-2b
=3(2x-3y)-2(x+4y)
=6x-9y-(2x+8y)
=4x-17y
=4+34
=38

The square of 2A + B of 3x - the square of 3a-2b of 5Y = 0
Finding the value of a and B

Multiply X-1 on both sides
3x=m
Increasing the root means that the denominator is 0
So X-1 = 0
x=1
Substituting 3x = m
m=3
240 yuan for Party A and 80 yuan for Party B
Then the deposit of two persons is 1000-240 + 80 = 1160 yuan
A is three times as much as B
So at this time, B has 1160 × 1 (1 + 3) = 290 yuan
290-80=210

If (3x ^ 2A + B + 1) + (5Y ^ a-2b-1) = 10 is a quadratic equation with respect to X and y, find the value of b-a

3x ^ (2a + B + 1) - 5Y ^ a-2b-1 = 10 quadratic equation with respect to x, y
So 2A + B + 1 = 1, a = 1
So B = 1-1-2a = - 2

If the diagonal length of a parallelogram is x, y and one side is 12, then the value of X, y may be ()
A. 8 and 14b. 10 and 14C. 18 and 20d. 10 and 34

A. 82 + 142 = 4 + 7 = 11 < 12, so impossible; B, 102 + 142 = 5 + 7 = 12 = 12, so impossible; D, 34-10 = 24, so impossible; so choose C

How to solve (8% * 300) / (300 + x) = (12.5% * 120) / (120 + x)

24\(300+x)=15\(120+x)
8(300+x)=5(120+x)
2400+8x=600+5x
3x=-1800
x=- 600

Let f (x) = SiNx - √ 3cosx + X + 1. Find the tangent equation of F (x) at x = 0
I've learned, but I've forgotten after a long time

The derivative of the above function is: cosx + √ 3sinx + 1, so when x = 0, the tangent slope is equal to his derivative (substituting zero into the derivative equation) = 2, find out f (x) = 1 - √ 3 when x = 0, and get y - (1 - √ 3) = 2 (x-0), which is the tangent equation here. Can you learn derivative? Well, use derivative, you can recite the derivation formula, which is a very basic topic

The rational number that is a negative number but not an integer is (), and the rational number that is neither a fraction nor a positive integer is ()

A rational number that is a negative number but not an integer is (negative fraction), a rational number that is neither a fraction nor a positive integer is (negative integer)

It is known that the function f (x) = 4x & sup3; + ax & sup2; + BX + 5 has extremum at x = - 1 and x = 3 / 2

The title is incomplete
According to the meaning of the question, the value of F '(x) is 0 at x = - 1 and x = 3 / 2, that is, f' (x) = 12x & sup2; + ax + B = 0 has roots - 1 and 3 / 2
Substituting it, we can get 12 + A + B = 27 + 3 / 2A + B = 0, a = - 30, and B is any real number

The reciprocal of 3 / 2 and the sum of 4 / 9 are more than 1 / 2 of a number. What is the number

Formula: (1 △ 3 / 2 + 4 / 9-1) △ 1 / 2
=(2/3+4/9-1)÷1/2
=1/9÷1/2
=2/9
Equation:
Let this number be X
1/2X+1=1÷3/2+4/9
1/2X=10/9-1
X=1/9÷1/2
X=2/9

Solution equation: 4Y ^ 2 + 25 = 20Y

4y^2+25=20y
4y^2-20y+25=0
(2y-5)^2=0
y1=y2=5/2