Question

Describe and correct the error in using the diagram to find the value of x.

Answer 1

Step-by-step explanation:

Hi there!

The error in using the diagram to find x in the solving is that they only picked two angles and equated to 180° which is wrong. You'll find out that their final value for x contains a decimal point which should never be in angles.

The above diagram is a revolution (360°) or angle at a point, so all the angles have to be considered and equated to 360° and NOT 180°

Below is the corrected solving.

$13x + 45 + 12x - 40 + 19x + 3 + 6x + 2 = 360$

(reason: angles at a point = 360°)

Collect like terms, and make x the subject of formula.

$⟹50x + 10 = 360$

$⟹50x = 360 - 10$

$⟹50x = 350$

Now, divide both sides by 50 to find the value of x.

$\frac{50x}{50} = \frac{350}{50}$

Therefore:

$x = 7$