The square of 4x + 1 is less than or equal to 4x

The square of 4x + 1 is less than or equal to 4x

4X square + 1 ≤ 4x
4X square - 4x + 1 ≤ 0
(2x-1) square ≤ 0
In this inequality, because (2x-1) square ≥ 0, we can only take the equal sign, that is, (2x-1) square = 0, x = 1 / 2

1. Solve the equation 2 and 1 / 7 + 2x = 3 and 1 / 5

15/7+2x=16/5
2x=112/35-75/35
2x=37/35
x=37/70

Find the function z = x ^ 2-xy + y ^ 2 in the region | x | + | y|

Find | x | + | y|

Xiao Ming has a drink, which is 1 / 5 liter
(1) How many times can I drink 1 / 10 liter at a time?
(2) How many times can I drink 1 / 30 liter each time?

1 / 5 divided by 1 / 10 = 2
1 / 5 divided by 1 / 30 = 6

C and D are reciprocal to each other. Simplify the Square D of C plus the square of D minus D / C minus C

0

The distance between Party A and Party B is 660 km. A passenger car drives from place a to place B at the speed of 50 km per hour. Two hours later, a freight car drives from place a to place B,
How many kilometers does the train travel per hour? (equation)

Pursuit problem
The train runs x kilometers per hour
50*（2+5）=5*x
x=7
It's a truck from B to a
Set up freight cars to travel x kilometers per hour
50*2+5(50+x)=660
100+250+5x=660
5x=310
x=62
A: trucks travel 62 kilometers per hour

The solving process of algebraic formula 1 / 2A square-2b square + 4AB
If the value of the algebraic formula (2x square + ax-y + 6) - (2bx square + 3x + 5y-1) has nothing to do with the value of the letter X, find the value of the algebraic formula half a square - 2b square + 4AB

The original formula = (2-2b) xsquare + (A-3) x-6y + 7 has nothing to do with X, so the phase coefficient of X is 0
So 2-2b = 0, A-3 = 0, so a = 3, B = 1
9 / 2-2 + 12 = 29 / 2

A and B drive from a to B, a's speed is 40 km / h, B's speed is 50 km / h, a drives for half an hour, find the distance between a and B
Another question: an airplane flies in two cities. When there is no wind, the airplane flies 550 kilometers per hour. In another round-trip flight, it takes five hours to go with the wind and six hours to go against the wind

It took x hours to set up B
0.5*40+40x=50x
x=2
So the distance is 50 * 2 = 100km
2. Set wind speed XKM / h
(550+x)*5=(550-x)*6
x=50
So the wind speed is 50km / h

Solving quadratic equation with one variable (29 + 2x) (22 + 2x) = 5 / 4 × 29 × 22

(29 + 2x) (22 + 2x) = 5 / 4 × 29 × 22
4x^2+2*(29+22)x+29×22-5/4×29×22=0
4x^2+2*(29+22)x-1/4×29×22=0
Using the formula of root
x=(-51±√2703)/4

The distance between the two places is 450 km. Car a and car B start from the two places at the same time and run in opposite directions. After five hours, they meet. The speed ratio of car a and car B is 5:4. What's the speed of car a and car B?

The speed of vehicle a is set at 5x km / h
The vehicle speed is 4xkm / h
5X*5+4X*5=450
The solution is x = 10
Speed of car a = 5 * 10 = 50 km / h
Vehicle B speed = 4 * 10 = 40 km / h
Hand only,