Find the value of x

a: 7
b: -7, 7
c: 49
d: -49, 49

Hi there! The answer is B. -7 or 7

The angles in a quadrilateral always add up to 360°. Therefore the angle of P is


So the angle of P is 49° and equals x^2. Therefore we get the following equation


Take the square root of both sides

OR


Since the angle must be positive, the value can as well be -7 as 7 (because the square of both of these numbers is 49°). Hence, the answer is B.

How many is in each case if there is 12 in each case it would be 40