Question

The value of X is??​

Answer 1

for this case we have that by definition, the sum of the internal angles of a traingule is 180 degrees.

In addition, the angle "R" of the triangle is given by:

$R = 180-45x$

So, we have to:

$(180-45x) + 25x + (57 + x) = 180\\180-45x + 25x + 57 + x = 180\\-45x + 25x + 57 + x = 0\\-45x + 25x + x = -57\\-19x = -57\\x = \frac {57} {19}\\x = 3$

Answer:

$x = 3$