X ^ 2 + MX + 4 is the square of a binomial about X, then the value of M is

X ^ 2 + MX + 4 is the square of a binomial about X, then the value of M is

x^2+mx+4=x^2+mx+2²
So m = 4 or - 4

We know that 9x ^ 2 + ax + 4 is the square of a binomial=_______ The binomial is______ .

A = 12 or - 12
The binomial is 3x + 2 or 3x-2

Mathematical application problem. According to the proportion, efficiency?
If the time ratio is 9:10, then the efficiency ratio is 10:9. If the sum of two people's efficiency in the original plan is 9, then the efficiency of Xiao Zhang will be 10 after 20% improvement, so the efficiency of Xiao Zhang is 5 and that of Xiao Wang is 4
How to get the efficiency of Yuan Xiaozhang? Please list the detailed formula

10－9＝1
1÷20％＝5
I hope it will help you

Simple operation of dividing 16 by 2.5
It's from primary school. Don't use any letter formula. Just use numbers!

16/2.5
=(16*2)/(2.5*2)
=32/5
=(30+2)/5
=30/5+2/5
=6 and 2 / 5

On the mathematics of shaking hands with everyone
At a party, everyone should shake hands with everyone else. If the total number of handshakes is 780, how many people are there at the party?
How did you come up with that?
Why divide by two for?

There are n people. One person shakes hands n-1 times. Total number = n * (n-1) / 2 (two people shake hands once, so divide by 2)
N=40

Simple calculation of 2.75 * 3.7 + 27.5 * 0.37
2.75 * 3.7 + 27.5 * 0.37 (simple calculation, * is a multiplier sign!)

2.75*3.7+27.5*0.37
=2.75*3.7+2.75*3.7
=2.75(3.7+3.7)
=2.72*7.4
=20.35

If x = 2Y = 1 and x = 1y = 2 are two sets of solutions of the equation MX + NY = 3, find the values of M and n

Substituting x = 2Y = 1 and x = 1y = 2 into MX + NY = 3, we get 2m + n = 3M + 2n = 3 (3 points), and the solution is m = 1, n = 1. (5 points)

-81 △ (- two and a quarter) × four ninths △ (- 16) =?

-81 △ (- two and a quarter) × four ninths △ (- 16)
=81÷9/4×4/9÷（-16）
=-36×4/9÷16
=-16÷16
=-1

What is the basis for solving the deformation of "merging similar terms" in the equation? What is the basis for "coefficient to 1"?

Basis of merging similar items: inverse operation of multiplication allocation rate
Transfer basis: equality property 1 (if the same number or formula is added or subtracted from both sides of the equation, the equal sign still holds)
The coefficient is changed to 1 according to the property of the equation 2 (if both sides of the equation are multiplied by a non-zero number or formula, the equal sign will still hold)

12+14+18+116+132+164+1128．

12+14+18+116+132+164+1128，=1-12+12-14+14-18+18-116+116-132+132-164+164-1128，=1-1128，=127128．