Question

please answer these questions ​

Answer 1

3)a) 3y - 10 + 2x = 180 => 2x + 3y = 190

      4x - 3y = 20

Adding above 2,

6x = 210, x = 35 degree

3y =  4x - 20 = 140 - 20 = 120

y = 40 degree

BOC = 70 degree

AOC = 110 degree

3)b) y = 45 degree ( vertically opposite angles )

       45 + 45 + 4x - 5 + x + z = 360

5x + z = 275

By,  vertically opposite angles

4x - 5 = x + z

3x = 5 + z => z = 3x - 5

When z is substituted in 5x + z = 275

8x = 280

x = 35 degree

z = 100 degree

4) Produce a line as shown.

Now, TOP angle is 180 as straight line,

So the condition will be true since both sides of line adds to 360 degree.