Make a game plan. ...
Make up numbers for segments and angles. ...
Look for congruent triangles (and keep CPCTC in mind). ...
Try to find isosceles triangles. ...
Look for parallel lines. ...
Look for radii and draw more radii. ...
Use all the givens.
The other form of circle equation is (x-a)2 + (y-b)2 = r2. a and b is the coordinate of the center and r is radius. So the equation is x2+(y-4)2=9. Change it to the general form is x2+y2-8y+7=0. So A=1, B=1, C=0, D=-8 and E=7.
Answer:
area of circle=πr²=3.14×5²=78.5unit²