Xiao Ming went to school from home. After walking at the speed of 50 meters per minute for two minutes, he found that he would be 8 minutes late if he walked at this speed Xiao Ming went to school from home. He walked at a speed of 50 meters per minute for two minutes. He found that he would be 8 minutes late if he walked at this speed. So he accelerated his pace and walked 10 meters more per minute. As a result, when he got to school, he had five minutes to go. What's the distance between Xiao Ming's home and school?

Suppose Xiaoming takes X minutes from home to school at a speed of 50 meters
50*x=50*2 (50 10)*(x-2-8-5)
The result is: x = 80
So Xiaoming's home to school: 50 * 80 = 4000 meters

There are 15 questions in total, 8 points for each right question, 4 points for each wrong question, and 72 points for Xiao Ming. How many questions did he do right?

8x-4 (15-x) = 72

Divide a polynomial [(17x2-3x + 4) - (AX2 + BX + C)] by (5x + 6), the quotient is (2x + 1), and the remainder is 0?

A polynomial [(17x2-3x + 4) - (AX2 + BX + C)] is divided by (5x + 6), and the quotient is (2x + 1), and the remainder is 0. Find ABC =? (5x + 6) (2x + 1) = 10x ^ 2 + 17x + 6 (17x2-3x + 4) - (10x ^ 2 + 17x + 6) = 7x ^ 2-20x-2, a = 7, B = - 20, C = - 2abc = 7 * (- 20) * (- 2) = 280

A simple algorithm of 72 * 53 + 41 * 24

72*53+41*24
=24*3*53+41*24
=(159+41)*24
=200*24
=4800

What are the points on the curve X & # 178; + xy-y & # 178; + 1 = 0

(0,1), (0, - 1) etc

(Mathematics of senior one) given that the solution set of inequality ax + b > 0 is (- ∞, 3), find the solution set of inequality (AX + b) / X ≤ 0

The solution set of (AX + b) / X ≤ 0 is the difference between X and (AX + b)
When ax + b > 0, X is needed

Vertical calculation of 124 times 17

1 2 4
× 1 7
————
8 6 8
1 2 4
————
2 1 0 8

lim(x→-∞）e^xsinx

e^xsin(x),
When x tends to negative infinity, e ^ x tends to e ^ (negative infinity) = 1 / e ^ (negative infinity). Because the denominator tends to infinity, the fractional value tends to 0;
At the same time, sin (x) oscillates between - 1 and 1. There is no limit, but it is a finite value;
How much is 0 times a finite value?
Obviously 0

In the quadratic equation 4x + 3Y = 7, if x and y are opposite numbers, then x = [], y = []

x=7,y=-7

1+12+123+1234… +What's 123456789?

137174205