Its simple. You collect like terms and put them on one side of the equation
Answer:
7
Step-by-step explanation:
formula for circumference of a circle is
d
7
=
d
d = 7
These angles are vertical angles meaning that they are equal to each other. Here is the equation for this problem:
x + 40 = 3x
Combine like terms
(x-x) + 40 = 3x - x
40 = 2x
Isolate x
40/2 = 2x/2
x = 20
Hope this helped!