So confused i trough it was 210 degrese but is not ...how?
can some one explain it to me ?

75 degrees

Step-by-step explanation:

Angle DEF is an inscribed angle, and by definition, an inscribed angle's degree measure is half the degree measure of the corresponding central angle.

Here, the corresponding central angle is DOF, which we see is 150 degrees. Then since <DEF = (1/2) * <DOF, <DEF = (1/2) * 150 = 75 degrees.

Hope this helps!

The answer is 77sq units. approx 28%

210 is the degree of the segment D but its not the area of one angle the opposite side E.

To find the area of a segment we need a formula.

Another way to do this to help you remember is count the radius measure =R2 but what = R2 answer is the points DE

Also we notice FD = R2

and EF also = R

so we have R2+R2 +R =R5

But as they are inwards we now have to draw a triangle point to subtract and then take away the arc circle area which we call arc1 and see a new arc we know it is 2x call that arc2 (means 2 x the value.

The new triangle = 180 degree and measures R1 and R1 add together = 2

We can use 7 + 7 = R1 add R1 as guide example and do the trigonometry

7 x 7 = 49 add the same = 98 square root of 98 = 9.898 which shows a ratio to the 7.

We can express this much better and its important you just write

Example R1 = 5  or R1 = 7 to show an easier ratio.

9.9 rounded to 7 = 1.29 scale enlargement one direction but we need to divide and multiply for all new representation. So we divide 9.898/7 =1.414 this our new scale.

So for showing all sides for the inverse we can write  R1, R1, R1 +1.29

Point D:F now is R1+1.29 is hypotenuse which we do need as we split the 180 into 90 2 points to the new arc and find base is now 4.45 if saying R1=7

Like above.or saying base of new arc line = hypotenuse1/2= base 1/2 = R1+0.77 which will be our multiplier. For 3.5, for every line from now on.

Area formula

= 1/2 b x h

= 4.949 x 7 (our radius side)=34.643sq 2

we times this by 2 for the second triangle = 69.286sq2 we

Calculating the Circle

To show area of whole circle and prove for area Pie x R1 x R2 = 3.14 x R1 x R1 so for 7 x 7 = 49sq3 x pi =

Calculating the lower part we want to deduct

= 153.86/2 as one half is below + 2 arcs =1/3 triangle.

=76.93 + 1/3 of 34.623

= 11.51

=88.44

Calculating the Upper part we take away the arc and + x 2 arc we create by drawing another triangle. They are now x3 arc size.

88.44 - 34.623 and - 69.623 = -15.806  

We therefore x 1/10 of square R to find the degree

15.806 x 4.9 = 77.494. E angle

Which is the same as 15.806 we just used smaller numbers to represent R and need even smaller numbers now we multiplied.

7 units the radius = 30.003

Compare to the Area of a circle 153.86 and radius R1 = 7

Reverse Area of segment = 77.44 degree.

When we use formula we find A = (½) × r 2 × [(π/180) θ – sin θ]

We check 1/2 x 49 x pi =  24.5 x 3.14 = 76.93 then x 0.0174 then take away the angle you found 90+90-36 = 144 for example when you multiply it to the 0.01174 you find the area.

Step-by-step explanation:

more detail

step-by-step explanation: