Attachment 18442

i want to know how to solve this question to find the x in it.And with explanation as i don't know how to solve it.

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- Aug 4th 2010, 05:26 PMhaftakhanFinding unknown angle
Attachment 18442

i want to know how to solve this question to find the x in it.And with explanation as i don't know how to solve it. - Aug 4th 2010, 05:57 PMeumyang
Is that a parallelogram with its lower left corner "cut off"? If so, then imagine that you have this corner. It would form a triangle, with two of angles being are supplemental angles of 3x and 132°. The 3rd would have be 2x.

The sum of these angles is 180°, so the equation is

$\displaystyle (180^{\circ} - 3x) + 48° + 2x = 180^{\circ}$.

Solve for x. - Aug 4th 2010, 08:12 PMhaftakhan
where has 48 come from ?

- Aug 4th 2010, 08:53 PMeumyang
- Aug 7th 2010, 03:11 AMhaftakhan
Can u explain it in detail as i cant understand it

- Aug 7th 2010, 06:16 AMeumyang
Look at the attached diagram:

Attachment 18467

I've added a "corner" to the parallelogram in your original drawing, and then I enlarged the corner. I'm assuming that this "corner" forms a triangle. The sum of angles**a**,**b**, and 2x has to equal 180°.

Angle**a**is the supplement of 3x, so $\displaystyle a = 180^{\circ} - 3x$. Angle b is the supplement of 132°, so $\displaystyle b = 180^{\circ} - 132^{\circ} = 48^{\circ}$. Therefore, the sum of the angles in this triangle is

$\displaystyle (180^{\circ} - 3x) + 48° + 2x = 180^{\circ}$.