Question

Can’t work out angle 2x-30 I don’t know what this means and is the angle next to 68 a right angle or straight line : would I subtract 180 - 68

Answer 1

x = 63

Explanation:

Since AB and CD are parallel lines, then

2y - 30 = 68 ( corresponding angles )

Add 30 to both sides

2y = 98 ( divide both sides by 2 )

y = 49

The third angle in the triangle = 68 ( alternate angles )

The sum of the 3 angles in the triangle = 180°, that is

x + y + 68 = 180 ← substitute value of y

x + 49 + 68 = 180

x + 117 = 180 ( subtract 117 from both sides )

x = 63

Answer 2

x = 63 degrees.

Explanation:

So first, 2y - 30 = 68 degrees.

It is because of alternative interior angles.

2y - 30 = 68

2y = 98 Move the -30 to the other side

98/2 = 49 So, y = 49

So in a triangle, the 3 angles equal 180 degrees.

So you do 49 + 68 = 117 degrees. You do this, because the 2 angle not including x is 49 and 68

Then you subtract 117 from 180

180 - 117 = 63 degrees. You do this because the 3 angles of a triangle equal 180 degrees.

So x = 63 degrees