Question

Q9.ABCD is a parallelogram .if angle A =(3x -20)°and angle C = (x + 40)° then the value of x is_____​

Answer 1

$\underline{ \: \: \bold{\orange {Solution :-}}}$

As in a Parallelogram the sum of opposite angles is 180° .

then,

$\sf➠ ∠ A + ∠ C = 180$

$\sf➠ \: (3x - 20) + (x + 40) = 180$

$\sf➠ \: 3x + x - 20 + 40 = 180$

$\sf➠ \: 4x + 20 = 180$

$\sf➠ \: 4x = 180 - 20 = 160$

$\sf➠ \: x = \frac{160}{4}$

$\sf \red➠ \: \boxed{ \orange{ \sf\: x = 40}}$