Question

the center of a circle is (2a-1 7) and it passes through through the point (-3,-1) . if the diameter of the circle it 20 units , find the value of p.​

Answer 1

Answer:

Since the circle with centre (2a-1, 7) passes through the point (-3,-1)

The Distance between (2a-1, 7) and (-3, -1) is the Radius of the circle...

Given,

Diameter = 20 units

Therefore,

Radius = 10 units

By Distance Formula (Co-ordinate Geometry):

10. =sqrt{(2a-1 -(-3))^2 + (7-(-1))^2}

100=(2a+2)^2 + 64

100=(2a)^2 + 4 + 8a +64

100=4a^2 + 8a +68

0=4a^2 + 8a -32

0=4a^2 +16a-8a -32

0=4a(a+4)-8(a+4)

0=(4a - 8)(a + 4)

Therefore,

a=8/4. Or. (a = - 4)

(a=2) or p = 2