The process of solution of X + 1.4x equation

The process of solution of X + 1.4x equation

Extract x into x (1 + 1.4) to solve

X=1.4X－6.4
X=1.4X－6.4

6.4=1.4×－×
6.4=0.4×
×=6.4÷0.4
×＝16

Find the answers of two practical problems and three equations. The calculation process should be detailed. If the equation is used, the calculation process of the equation should also be detailed
Practical questions
1. The male students in a certain grade are 7 / 8 of the female students. Recently, another male student came in. As a result, the male students are 8 / 9 of the female students. How many students are there in the whole grade now?
2. Party A and Party B build a section of highway from both ends at the same time and meet at a distance of 15 meters from the central point. It is known that Party B builds 40% of the total length of the highway. How many meters is the total length of the highway?
solve equations
1.7x=28/15+3x 2.60%x=3/4x-3/2 3.9.6x=8x+32

1. Suppose the number of female students is x, then: 7 / 8x + 1 = 8 / 9x8 / 9x-7 / 8x = 11 / 72x = 1 x = 72. There are 72 + 8 / 9 * 72 = 136 students in the whole grade. 2.15 / (1 / 2-40%) = 15 / 10% = 150 meters. Solve the equation: 7x = 28 / 15 + 3x7x-3x = 28 / 154x = 28 / 15x = (28 / 15) / 4x = 7 / 1560% x = 3 / 4x-3 / 23 / 4x-60% x = 3 / 215% x = 3 / 2x = (3 / 2)

Given the function f (x) = 2asin (2x - π 3 / 2) + B, the maximum value of the function is 1, and the minimum value is - 5 (1). Find the value of a and B
(2) When the domain is {0, 2 / π}, the values of a and B are obtained

f(x)=2asin(2x- 3／π）+b
When sin (2x - 3 / π) = 1, the maximum f (x) is 2A + B = 1
When sin (2x - 3 / π) = - 1, the minimum f (x) is - 2A + B = - 5, and a = 3 / 2, B = - 2 can be solved simultaneously

If f (x) = x & # 178; - 2mx + 4m-8, the vertex is a, and an inscribed regular triangle ABC is made in the parabola, what is the relationship between the area of positive △ ABC and M?
I hope there is a specific process

The coordinate of vertex A is (m, - M2 + 4m-8) △ amn is the inner angle regular triangle of parabola, the intersection symmetry axis of Mn is at point B, then AB = radical 3, BM = radical 3, BN, let BM = BN = a, then AB = radical 3a, ∵ the coordinate of point m is (M + A, radical 3a-m2 + 4m-8), ∵ point m is on the parabola, ∵ radical 3a-m2 + 4m-8 = (M + a) 2-2m (

The rational numbers a, B, C are not 0, and a + B + C = 0, try to find the value of (| a | b) / (a | B | + (| B | C) / (B | C | + (| C |) / (C | a |)

If A0 and B can be positive or negative, then the original formula = - B / | B | + | B | / B-1. Whether B is positive or negative, the result is - 1

(5X-1200)×13/10=4X-1000
There's someone who can solve this equation

65X*15600=40X-10000
25X=5600
X=224

The problem of solving equations in primary school mathematics~~~
3x ^ 2-6x + 2 = 0 how to solve? To detailed steps, thank you... Just learned this, more confused

3 (x ^ 2-2x) + 2 = 0 3 (x ^ 2-2x + 1-1) + 2 = 0 3 [(x-1) ^ 2-1] + 2 = 0 3 (x-1) ^ 2-3 + 2 = 0 3 (x-1) ^ 2 = 3-2 = 1 (x-1) ^ 2 = 1 / 3, so X-1 = root (1 / 3), or X-1 = - root (1 / 3), that is, x = 1 + root (1 / 3), or x = 1 - root (1 / 3)

Given that a and B are the two real roots of the equation x & # 178; - 2x-2011 = 0, find the value of a & # 178; + B

Using Weida's theorem, a + B = 2Ab = - 2011, the title should be wrong, a & # 178; + B & # 178; = (a + b) &# 178; - 2Ab = 4 + 2 * 2011 = 4026, so. (x-1) &# 178; = 2012x-1 = ± √ 2012 = ± 2 √ 503x = 1 ± 2 √ 503 (1) a = 1 + 2 √ 503, B = 1-2 √ 503A & # 178; + B = 1 + 2012 + 4 √ 503 + 1-2 √ 503 = 201

What's the difference between "C" and "CE" on the calculator?
After pressing it, it will all return to zero

Press CE key, just clear the current input data or symbols, for example: calculate 4 + 2, enter 4 + 3, find 2 input wrong. At this time, press CE key, clear 3, and then enter 2, you can calculate the result
Press the C key, it means all zeros