Answer:
x = 30
Explanation:
The perpendicular bisector is cutting a line at a right angle, two sides of the line will be equal to each other which allows us to write the following equation:
2x - 20 = 70 - x transfer like terms to the same side of the equation:
2x + x = 70 + 20 notice how the signs of the expressions changed from "-" to "+" when transferred
3x = 90 divide both sides by 3
x = 30