Given that AD and BC are parallel, find the value of x.
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Answer:
Therefore the value of x is 15.
Step-by-step explanation:
Given:
AD || BC
m∠ B = (9x + 15)°
m∠ A = (3x - 15)°
To Find:
x = ?
Solution:
AD || BC ...............Given
If two lines are parallel and sum of the interior angles are supplementary.
i.e m∠ B and m∠ A are interior between Parallel lines.
∴ [tex]\angle B + \angle C =180\\[/tex]
Substituting the given values we get
∴ [tex](9x + 15)+( 3x - 15)=180\\12x=180\\\\x=\frac{180}{12} \\\\\therefore x =15[/tex]
Therefore the value of x is 15.