Answer:
x = 90
y = 100
z = -10
Explanation:
To find x and y in the above parallelogram ABCD as shown above, recall that one of the properties of a parallelogram is: the consecutive angles in a parallelogram are supplementary.
This means that the sum of angle A and angle B in the parallelogram ABCD = 180°.
Thus,
(x + 30)° + (x - 30)° = 180°
Solve for x
x + 30 + x - 30 = 180
x + x + 30 - 30 = 180
2x = 180
Divide both sides by 2
2x/2 = 180/2
x = 90
=>Find y:
Also, recall that opposite angles in a parallelogram are congruent.
This means, angle A and angle C in parallelogram ABCD above are equal.
Thus,
(x + 30)° = (y + 20)°
Plug in the value of x to solve for y
90 + 30 = y + 20
120 = y + 20
Subtract 20 from both sides
120 - 20 = y
100 = y
y = 100
=>Find z, if z = x - y
z = 90 - 100
z = -10