Math problems! Solve equations, solve equations mathematically, find math god solutions!!

1.(x+3)(x-4)(2x+1)=0, the root method, so the solution is x=2Extract the common factor (x+1) and simplify it to get (x+1) (x 2- 64) = 0, so the solution is x=

3. (x^3-3x^2) -2x-6)=0x^2(x-3)-2(x-3)=0

x-3)(x^2-2)=0

x=Hope mine is helpful to you.

I don't understand.

Good luck with your studies!

1) The result x1=-3,x2=4,x3=-(1 2) can be seen directly;

2) The original formula can be reduced to: (x+1)(x+8)(x-8)=0, so x1=-1, x2=-8, x3=8;

3) The original formula can be reduced to: x 2(x-3)-2(x-3)=(x-3)(x 2-2)=0; So x1=3,x2=-sqtr(2); x3=sqrt(2);

sqrt stands for square root.

x+3=0 or x-4=0 or 2x+1=0

So. x = -3 or 4 or -1 2

2.Propose that x+1 gives (x+1)(x 2-64)=0, so (x+1)=0, or (x 2-64)=0, so x=-1 or x=8 or x=-8

3.Propose (x-3) to get (x-3) (x 2-2) = 0, so (x-3) = 0 or (x 2-2) = 0

So x=3 or x=positive and negative root number two.

The system of equations with no solution x=-1, y=-1 is brought in, left = 1, right = -1, left is not equal to right. If you have learned the parabola, I will teach you an image method to judge the solution of the system of equations y=x 2 x 1 and draw a graph, and we can see him.

Big brother, what is the use of math?

Solution: If there are x male students, then there are (15-x) female students who get 70x-40 (15-x) = 60 according to the question

70x-600+40x=60

110x=660

x=6A: There are 6 male students.

One formula with two unknown quantities, you can't find it!

400+2s=560t+400

s=280t

The solution is that n is equal to 1, and the commutation method can be used, please see ** for the detailed process.

a), both sides of the equation are squared at the same time, and the following is obtained

4t+1=9-18t+9t²

9t²-22t+8=0

9t²-2*3*11/3t+(11/3)²=121/9-72/9=49/9

3t-11/3)²=(7/3)²

3t=7/3+11/3

t=2b), the root number 4x=x-3 both sides are squared at the same time, and the following is obtained

4x=x²-6x+9

x²-10x+25=16

x-5)²=4²

x=9c), root number (x+1)=x+1 both sides are squared at the same time, and the following is obtained

x+1=x²+2x+1

x²+x=0

x(x+1)=0

x=0 or x=-1

d), both sides are squared at the same time, get:

9x+117=x²+18x+81

x²+9x-36=0

x+12)(x-3)=0

x=-12 or x=3

Just square it and put the one with the root number aside. Then note that the root satisfies the defined domain.

a) The square of both sides yields 4t+1=(3-3t) squared.

4t+1=9-6t+9t squared.

9t squared - 10t + 8 = 0

b) Root number (4x) = x-3

The two sides are squared to get 4x=(x-3) squared.

c) Root number x+1=x+1

The two sides are squared to get x+1=x+1) squared.

d) The square of both sides gives 3x+39=(x+9) squared.

1. Set up a boat from A to B to share x hours, then B to C share (7-X) orange peel hours.

Circle auspicious difference * (7-x) = 10

x=, then the distance between the two piers of ab is kilometers.

2. If the length of the first banquet-type bridge is x meters, the length of the second bridge is (2x-50) meters, and the speed of the train is 10 meters per second.

2x-50）-x〕/10=5

If x=100, the length of the first bridge is 100 meters, and the length of the second bridge is 2*100-50=150 meters.

1. If the payment time in the first two payment methods is x years, the payment number of the first payment method is: 4 1 (x 1), and the payment number of the second payment method is: 4 (x 1) (

Solution: x 12 4 (x 1) 15 15 So A has to pay a lump sum of 10,000 yuan.

2. Set the time of transcendence to t hours, according to the title: (The car in the question is 4 kilometers long, it should be wrong, and it is replaced by 4 meters.) ）

110t 100t (12+4) 1000 (12 is the length of the truck, 4 is the length of the car, 12 4 is divided by 1000 is to convert the meter into kilometers, and the equation uses the distance traveled by the car to be 16 meters more than the distance traveled by the truck).

Solution: t hours) hours and seconds.

3. If the boss buys a tie x strip, then (1) the payment required for the plan is: 200 20 (x 20) 40, (2) the payment required for the plan is: (200 20 x 40) 90%, according to the title:

200 20 (x 20) 40 (200 20 x 40) 90% solution: x 100

4. 1 meter per hour.

Let the speed of the train be x meters and seconds, according to the title: 15 (x+1) 17 (x 1) (using the same body length).

Solution: x 16 (s) 15 (x+1) 255 (m).

The result of the fifth question is x

x-2+x+2+ x/2 +x x 2=99x=22

22x2=44

Let the last five digits be x

The original six-digit number is 100,000+x

The new number is 10x+1

10x+1=3(100000+x)

x=42857

The new number is 428571

The original number is 142857

Let the original number 1abcde and the current number abcde1 their relationship be 3 times.

1abcde * 3 =

abcde1 ……If there is 1 in e*3, then e is 7 (align the single digit of the original number with the single digit of the variable).

So 1abcd7

abcd71

1abcd7*3 = (align position look).

abcd71 ……Start with the single digit of the original number: 7*3=21 but e=7......71=21+50, then d*3 gives 5, so d=5

So 1abc57

abc571

1abc57 * 3 =

abc571 ……Then there are the tens of digits 5*3=15 but d=5......57=15+42 Then c*3 gives 4, so c=8

So 1ab857

ab8571

1ab857 * 3 =

ab8571 ……Hundred: 8*3=24 but c=8......85=24+61, then b*3 gives 6, so b=2

So 1a2857

a28571

1a2857 * 3 =

a28571 ……Thousands 2*3=6 but b=2......28=6+24 Then a*3 gives 2, so a=4

So 142857

The original number is 142857

Because each price is the same, let the unit price be x, then (6+9)x=, and find x=yuan.

(three-quarters - three-fifths)*x=36

Three-twentieths * x = 36

x=240

Solution: The original question is like this: 3x 4—36=3x 53x 4-3x 5=36

3*(5-4)x/20=36

Solution x=240