Solve the equation 25X & # 178; - 49 = 0

Solve the equation 25X & # 178; - 49 = 0

25x²=49
x²=49/25
x=+-7/5

Find the value of X in the following formulas: (1) x2-25 = 0 (2) 4 (x + 1) 2 = 81 (3) 4x2 = 64 (4) x2 / 2-98 = 0

（1）x ² - 25 = 0
x ² = 25
x = ± 5
（2）4（x + 1）² = 81
（x + 1）² = 81 / 4
x + 1 = ± 9 / 2
x = ± 9 / 2 - 1
（3）4 x ² = 64
x ² = 16
x = ± 4
（4）x ² / 2 - 98 = 0
x ² / 2 = 98
x ² = 196
x = ± 14

X2 = 25 / 81

X = 5 / 9
Because 5 out of 9 times 5 out of 9 = 25 out of 81

There are four Arabic numerals, the first number plus 3, the second number minus 3, the third number multiplied by 3, and the fourth number divided by 3,
The results are all equal. We know that the sum of the four numbers is 96. What are the four numbers?

96/(3+3+3/(1/3)+1)=96/(3+3+9+1)=96/16=6
6*3+3=21
6*3-3=15
6*9=54
These four numbers are 15, 21, 6 and 54 respectively

On both sides of the equation 7y-6 = 3Y___ We get 4Y = 6, which is based on_________ .

On both sides of the equation 7y-6 = 3Y_ -3Y+6__ We get 4Y = 6, which is based on_ The principle that the two sides of an equation add or subtract a number or a formula at the same time________ .

-8 + 9; - 15 + (- 6); - 18 + 28; - 21 / 4 + 2.25; 12 + (- 5) + 10 + (- 16); 23 + (- 11) + 6 + (- 22)?

1、-8+9=9-8=1
2、-15+（-6）=-（15+6）=-21
3、-18+28=28-18=10
4、-21/4+2.25=9/4-21/4=-12/4=-3
5、12+（-5）+10+（-16）=12-5+10-16=22-21=1
6、23+（-11）+6+（-22）=23-11+6-22=-4

Given that a & # 178; - 3A + 1 = 0, then find the value of 2A & # 178; - 5a-2-3 / (1 + A & # 178;)

∵a²-3a+1=0
∴2a²-6a+2=0
∴2a²-5a=a-2
∵a²-3a+1=0
∴a²+1=3a
2a²-5a-2-3/(1+a²)
=a-2-2+3/3a
=a-4+1/a
=(a²+1-4a)/a
=(3a-4a)/a
=-a/a
=-1
I don't know how to ask~

You fill the nine numbers - 2, - 1, 0, 1, 2, 3, 4, 5, 6 into the nine spaces in the graph, so that the three numbers in each row, the three numbers in each column, and the three numbers in diagonal angles add up to 6

According to the analysis, it can be concluded that:

Using addition subtraction elimination method to solve the equations: 2S + 3T = 2 2s-6t = - 1

2s+3t=2.(1)
2s-6t=-1.(2)
(1) - (2), get
9t=3
T = 1 / 3, substituting in (1) to get
s=1/2

Girl (line diagram)
There are 24 boys, one fifth less than girls.)
Number of girls required
To solve the equation~
I can't understand the first floor, if I can't help it
The real estate market equation!
-4-equation!
-5 - it's written!

You didn't say that earlier
Girls x Boys 4 / 5x
4/5x=24
x=30
It's just + X