Question:
Tick (✓) the correct answer
Two adjacent angles of a parallelogram are (2x + 25)° and (3x − 5)°. The value of x is
(a) 28
(b) 32
(c) 36
(d) 42
Solution:
(b) 32
We know that the sum of adjacent angles of a parallelogram is $180^{\circ}$.
$\Rightarrow 2 x+25+3 x-5=180$
$\Rightarrow 5 x+20=180$
$\Rightarrow 5 x=180-20$
$\Rightarrow 5 x=160$
$\Rightarrow x=\frac{160}{5}$
Therefore, the value of $x$ is 32 .