When x = - 1, the value of the square of the algebraic formula - 3x + ax-7 is 7. When x = - 3, the value of the algebraic formula can be obtained

When x = - 1, the value of the square of the algebraic formula - 3x + ax-7 is 7. When x = - 3, the value of the algebraic formula can be obtained

-3*[-1]^2+a[-1]-7=7
-3-a-14=0
a=-17
X = - 3,
-3*【-3】^2-17*[-3]-7
=-3*9+51-7
=-27+44
=17

When x = - 3, the value of the third power + ax-7 of the algebraic formula - 3x is - 25. When x = 3, what is the value of the algebraic formula?

When x = - 3, the algebraic formula - 3x & sup3; + ax - 7 = - 25, that is, when x = - 3, the algebraic formula - 3x & sup3; + AX = - 18. Through observation, we can see that the algebraic formula - 3x & sup3; + ax is just opposite to the original formula when substituting - x, that is, when substituting - x, its value is - (- 3x & sup3; + ax)

List the equation: a number greater than 5 is equal to 8___ ．

The number 5 greater than a equals 8, which is expressed as a + 5 = 8 or a = 8-5

Li Li and Zhang Hua agreed to go to his home to do their homework tomorrow

Change "he" to "Li Li" or "Zhang Hua"

Is 1900 a leap year? 1904 a leap year, 1896 a leap year,
For this problem, I argued with my teacher for a long time,

In the leap year of the Gregorian calendar, there are one leap every four years, 97 leap every 400 years and 969 leap every 4000 years
Leap year arrangement:
① For example, 04, 08, 12, 16, 96. This year is 12, which is a leap year, and next year is 13, which is not leap year. The next leap year should be 2016
② For example, 2000 is a leap year, 1900 and 2100 are not
③ By 4000 A.D., although it can be divided by 400, it is not a leap year
So 1900 is not a leap year. 1904 and 1896 are leap years

Three times one third equals one. That's 0.33333 Multiply by three to get

1

In a cross-country race, when Xiaoming ran 1600m, Xiaogang ran 1450m. After that, they adjusted their speed and ran at their own new speed. After 100s, Xiaogang overtook Xiaoming, 200s, 300s, Xiaogang reached the finish line. Their running time t (s) and distance are shown in figure s (m). The whole course of the cross-country race is______ m？

Suppose the speed of Xiaoming and xiaogangxin are XM / s and YM / s, respectively. From the meaning of the question, we get 100y − 100x = 1600 − 1450, ① 200y − (1600 − 1450) = 300X, ②, y = x + 1.5, ③, ②, 4y-3 = 6x, ④, ③ into ④, 4x + 6-3 = 6x, and the solution is x = 1.5

Translation from English to Chinese
First, some engineers make TVs sound better. Second, some keep money of stores safe. Third, almost everyone reads the Sunday paper.Usually the paper is very thick.There are advertisements and many different part.Old people read the notices.Children like interesting stories, So the children like reading them!

Some engineers make TVs sound better. Some engineers make TVs sound better. Some keep money of stores safe. Almost everyone reads the Sunday paper

When gardeners use scissors to trim branches, they often put the branches as close as possible to the scissors axis o
A. The resistance arm can be reduced to save labor
B. The power arm can be enlarged to save labor
C. The work done to overcome resistance can be reduced
D. It can reduce the work done by power

Choose B for this topic
ACD correct

The total length of the edges of a cuboid is 96 cm, the length is 9 cm, the width is 8 cm and the height is 10 cm______ Cm

96 △ 4 - (9 + 8), = 24-17, = 7 (CM); answer: the height is 7 cm