Answer:
b = -3
Step-by-step explanation:
-13 = 2b - b - 10
Add 10 to both sides of the equation
-3 = 2b - b
Subtract 2b - b
-3 = b
b = -3
Hope this helps :)
Answer:
see explanation
Step-by-step explanation:
(5)
Since ∠EBA = 90° then ∠ABD = 90° ( straight angle ) and
∠ABC + ∠CBD = ∠ABD, that is
2x + 3x - 10 = 90, simplifying
5x - 10 = 90 ( add 10 to both sides )
5x = 100 ( divide both sides by 5 )
x = 20, thus
∠ABC = 2x = 2 × 20 = 40°
∠CBD = 3x - 10 = (3 × 20) - 10 = 60 - 10 = 50°
(6)
4x - 18 = 3x + 7 ( vertical angles are congruent )
Subtract 3x from both sides
x - 18 = 7 ( add 18 to both sides )
x = 25
7y = 5y + 28 ( vertical angles are congruent )
Subtract 5y from both sides
2y = 28 ( divide both sides by 2 )
y = 14
Answer:

Step-by-step explanation:
Given expression:

Substitute

into the expression:

Answer:
10
Step-by-step explanation:
radius is the middle point of a circle, therefore divide it in half.