Solution equation: X / 30 + 15 / 60 = x / 18-15 / 60

X / 30 + 15 / 60 = both sides of X / 18-15 / 60 multiply by 180 at the same time to get
6x+45=10x-45
10x-6x=45+45
4x=90
x=90÷4
x=22.5

sin53°cos37°+cos53°sin37°=______ ．

The original formula is: sin53 °· sin53 ° + cos53 °· scos53 ° = sin253 ° + cos253 ° = 1

80 is 60% more than a number. How to find this number

Let this number be X
Then x + 60% x = 80
The solution is x = 50

My mother bought a 120 page new book for Xiaojun. Xiaojun read 96 pages in three days. Xiaojun read several parts of the book in three days

96/120=4/5
Xiaojun read four fifths of the book in three days

In the plane rectangular coordinate system, there is a point a (- 2,1), B (3,1) C is a point on the coordinate axis. If △ ABC is a RT triangle, find the coordinate of point C

Obviously, the line AB is parallel to the x-axis, and neither AC nor BC can be perpendicular to ab. therefore, AC is perpendicular to BC. If C is on the x-axis, let it be (x, 0), then (x + 2) (x-3) + (0-1) (0-1) = 0. If C is on the y-axis, let it be (0, y), then (0 + 2) (0-3) + (Y-1) (Y-1) = 0, then y = 1 ± √ 6

How many milliseconds per year

365*24*60*60*1000=3.156X10^10

Find the hyperbolic equation with the focus of 9 / y square plus 16 / x square equal to 1 as the vertex and the focus of ellipse as the vertex

The focus of an ellipse where 9 / y squared plus 16 / X squared equals 1, (0, - 7) (0, √ 7)
Ellipse C = √ 7 A = 4
Hyperbola C = 4 a = √ 7 B ^ 2 = C ^ 2-A ^ 2 = 9
Hyperbolic equation y ^ 2 / 7-x ^ 2 / 9 = 1

Given the function f (x) = 2sinxcosx-2cos & # 178; X + 1 + √ 3, find the minimum positive period and maximum value of F (x)

f(x)＝2sinxcosx-2cos²x+1+√3
＝2sinxcosx-(1+cos2x)+1+√3
＝sin2x-cos2x+√3
＝√2sin(2x-π/4)+√3.
Minimum positive period: T = 2 π / 2 = π;
Maximum: F (x) | max = √ 2 + √ 3;
Minimum: F (x) | min = - √ 2 + √ 3

Through the point P (1,2), make the positive half axis of X, Y axis at a, B, and find the equation of the line when the area of triangle AOB reaches the minimum

Let the linear equation be x / A + Y / b = 1,
Then 1 / A + 2 / b = 1
And 1 / A + 2 / b ≥ 2 √ [2 / (AB)]
∴1≥2√[2/(ab)]
If and only if 1 / a = 2 / b = 1 / 2,
That is, when a = 2, B = 4, the equal sign holds
∴S=ab/2≥4 ．
S min = 4
x/2+y/4=1
2x+y-4=0

Solution equation: X / 30 + 15 / 60 = x / 18-15 / 60