B. In the figure given below, find the value of the angle x.
Px
70°
602

The value of the angle x is 140°

Step-by-step explanation:

In the given figure

∵ The figure has 4 sides

∴ The figure is a quadrilateral

∵ The measure of the interior angle of the quadrilateral is 360°

∴ The sum of the angles inside the quadrilateral = 360°

∵ One of the vertices of the quadrilateral has an exterior angle of

   measure 90°

∵ The sum of the interior angle and the exterior angle at a vertex = 180°

∴ The measure of the interior angle = 180° - 90°

∴ The measure of the interior angle = 90°

∵ The measures of the interior angles of the quadrilateral are 60°, 70°,

    x, 90°

∴ 60° + 70° + x + 90° = 360°

→ Add the like terms in the left side

∴ 220° + x = 360°

→ Subtract 220 from both sides

∴ 220 - 220 + x = 360 - 220

∴ x = 140°

∴ The value of the angle x is 140°