Answer:
Explanation:
8) looking at the figure at number 8,
It is a quadrilateral. In a quadrilateral, the opposite angles are supplementary. This means that the sum of all the angles is 360 degrees. We have assigned y degrees to the remaining unknown angle.
y = 180 - 71 = 109 degrees( this is because the sum of angles on a straight line is 180 degrees.
Therefore
10x + 6 + 8x - 1 + 13x - 2 + 109 = 360
31x + 112 = 360
31x = 360 - 112 = 248
x = 248/31 = 8
9) looking at the figure, we have assigned alphabets a, b and c to represent the inner angles that form the triangle.
a + 9x + 1 = 180
a = 180 - 1 -9x = 179 - 9x(this is because the sum of the angles on a straight line is 180 degrees)
b + 5x + 12 = 180
b = 180 - 12 - 5x
b = 168 - 5x
c + 10x -37 = 180
c = 180 - 10x + 37
c = 217 - 10x
a + b + c = 180( sum of angles in a triangle is 180 degrees)
179 - 9x + 168 - 5x + 217 - 10x = 180
-9x - 5x - 10x = 180 - 179 - 168 - 217
-24x = -384
x = -384/-24
x = 16