Question

7c+36
5c+40
Find x
X

Answer 1

x = 130

Explanation:

7c + 36 and 5c + 40 are vertically opposite angles and are congruent , so

7c + 36 = 5c + 40 ( subtract 5c from both sides )

2c + 36 = 40 ( subtract 36 from both sides )

2c = 4 ( divide both sides by 2 )

c = 2

Then

7c + 36 = 7(2) + 36 = 14 + 36 = 50

5c + 36 and x are a linear pair and sum to 180° , that is

50 + x = 180 ( subtract 50 from both sides )

x = 130

Answer 2

130 degrees

Explanation:

When two lines intersect, the opposite angles are equal, therefore, in this example, 7c+36 = 5c+40. We can find c using this equation.
7c+36 = 5c+40
7c-5c = 40-36
2c = 4
c = 4/2 therefore c=2

now that we know c is equal to 2, we can find out both of those angles.
therefore 5c+40 = (5*2)+40 = 10+40= 50
and 7c+36 = (7*2)+36 = 14 +36 = 50

now we know that those two angles add up to 100.

to find the sum of x and the angle opposite to x, subtract 100 from 360
360-100 = 260

since the angle opposite of x is equal to x, x+x = 260
2x=260
x=260/2 = 130

x is 130 degrees