Answer:
Step-by-step explanation:
If our interval is between 0 and 90 degrees, that means that our angles are first quadrant angles. Since the formulas for the half angles of sin and cos consider both the positive and negative roots, knowing that we are in QI leaves us using only the principle, or positive, root.
Also, if we know that the sin of angle is 3/4, we can set up a right triangle in QI and find the missing side of that triangle using Pythagorean's Theorem. Sin of an angle is the ratio opposite side/hypotenuse. That means that, according to Pythagorean's Theorem,
and
and
Now for the forula for the sin of a half-angle:
Referring to the right triangle we created and found the missing side for, we see that the cosine of that same triangle is 
Filling in the formula then:
Get a common denominator on the upper fraction:
Bring up the 2 as 1/2 to multiply and get:
When you do the exact same thing to find the cos of the half angle, you are using a + sign instead of a - sign under the radical. That gives you as your exact value:
Hi there!
The general formula to find the perimeter of a rectangle is :
P = (Length × 2) + (Width × 2)
Let's say the width of the rectangle is "x".
The lenght of the rectangle is equal to 2x + 4.2
Replace everything you know in the formula :
42.6 = ((2x + 4.2) × 2) + ((x) × 2)
Simplify everything :
2x × 2 = 4x
4.2 × 2 = 8.4
x × 2 = 2x
42.6 = 4x + 8.4 + 2x
42.6 = 6x + 8.4
Isolate "x":
42.6 = 6x + 8.4
Subtract 8.4 from each side of the equation
34.2 = 6x
Divide each side of the equation by 6
5.7 = x
5.7cm = the width of the rectangle
Since the lenght of the rectangle is equal to 2 times the width of the rectangle plus 4.2 :
Length = (2 × 5.7) + 4.2
Length = 15.6cm
42.6 = (2 × 15.6) + (2 × 5.7) ? → YES
There you go! I really hope this helped, if there's anything just let me know! :)
Basically your going to substitute x for 5 then multiply by 2 which is 10.After subtract 10 from 1 which is 9, so g = 9. I hope I answered your question
You have to break it up into individual pieces.
First, find the area of the inner triangle. The area of a triable is 1/2(base•height). Since there's 2 right triangles, you can just do (base•height).
Triangle area=(5•12)=60
To find the area of the bottom semicircle, use the formula for area of a circle and then divide by 2 since it's half a circle. A=(pi)r^2. The radius in this case is 5 (half of 10.)
Area of bottom circle=25pi/2
To find the area of the remaining circle parts, since both the half-circles are equal, we can just find the area of one whole circle with those dimensions.
A=(6.5)^2(pi)
The total area of the whole figure will be those 3 components added together.
A=25pi/2+42.25pi+60 meters squared
Answer:
5,550 dollars
Step-by-step explanation:
