Answer:
12.57
Step-by-step explanation:
the formula for the area of a circle is 
the diameter is 2 times the radius, so dividing it by 2 gives you a radius of 2
substitute the 2 for the r in the formula and solve

4
≈12.57
Answer: A= 1,-5 b=5,-3
Step-by-step explanation: i dont have one
Answer:
28 degrees
Step-by-step explanation:
If two parallel lines are cut by a transversal, then the pairs of corresponding angles are congruent.The corresponding angles are the ones at the same location at each intersection.
In the figure ABD and EDF are corresponding angles. So they are equal
So equation the angle ABD and EDF , we get
(3x+4) = (7x-20)
Group the like terms,
3x-7x = -20-4
-4x = -24

x = 6
Thus BCD will be,
(6x - 8)
=>(6(6)-8)
=>(36-8)
=> 28 degrees
Answer:
-0.8 and -8.2
Step-by-step explanation:
To solve a quadratic you first need to have one side of the equation equal to zero (because x-intercepts are when y is zero).
4x^2 + 24x + 13 = 2x^2 + 6x
2x^2 + 18x + 13 = 0
Then you can use the quadratic formula to solve for x. You will then come to
-18 ± sqrt(220) / 4
This will simplify out (rounding to the nearest tenth) to -0.8 and -8.2