Quadrilateral abcd is inscribed in a circle with m< a = (x2)°, m< b = (7x - 10)°,
and
m< c = (3x)°.
what is m< d?

106°

Step-by-step explanation:

A quadrilateral inside a circle is a cyclic quadrilateral.

It means that the angles opposite are supplementary (add up to 180).

If we draw the quadrilateral ABCD, the angles A and C are supplementary and the angles B and D are supplementary.

Since we know A and C, we can write:

A + C = 180

x^2 + 3x = 180

x^2 +3x - 180 = 0

(x+15)(x-12) = 0

x= -15, or x = 12

Now, if we put x = -15, some angles become negative, so we disregard it and take x = 12.

Now finding B:

B = 7x - 10

B = 7(12) - 10

B = 74

We also know that B + D = 180, so:

B + D = 180

74 + D = 180

D = 180 - 74 = 106

i found two solutions,   n = 2 • ± √3 = ± 3.4641

step-by-step explanation:

make sure you have version 2.50

try looking in the very back of the book : )

step-by-step explanation:

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