Answer:
β = 140 - α
we know that the "missing" angle is 40° since 40 + 140 = 180
we also know that the total sum of angles in a triangle is 180
so β = 180 - 40 - α
or β = 140 - α
Step-by-step explanation:
The answer is C that is X=7 and X=-1
multiple x through the given equation to get rid of a fraction. It will be

After that bring 6X to the LHS of the equation
so that it will look like the general equation that is

Use the quadratic formula (or any other approach to find the values of x
You will arrive at

Answer:
C = 24.5 in
Step-by-step explanation:
Formula to find the circumference of a circle is :
C = 2πr
Here,
r ⇒ radius
So let us solve now.
C = 2πr
C = 2 × π × r
C = 2 × 3.14 × 3.9
C = 24.492 in
So, they've asked for nearest 10th.
Therefore, the answer will be 24.5 in.
Hope this helps you :-)
Let me know if you have any other questions :-)