No solutions
Set equations equal to each other
-3.5x - 3.5 = -3.5x + 3.5
The -3.5x on both sides of the equation cancels out, leaving
-3.5 = 3.5
But -3.5 does NOT equal 3.5, so the solution to the system of equations is false. This means that there are no solutions.
Complementary angles --- they add up to 90 degrees
Given:
The diameter of a circle = 20 feet
To find:
The exact circumference of the circle.
Solution:
We know that the radius is half of the diameter of the circle.
The diameter of a circle is 20 feet. So, the radius of the circle is 10 feet.
The circumference of the circle is:
Where, r is the radius.
Substituting , we get
Therefore, the exact circumference of the circle is 62.8 feet.
Note: All options are incorrect.