Answer:
D
Step-by-step explanation:
The formula in computing the area of the circle is:
A = pi (r)^2
Where r = the radius of the circle
Since you are only given the diameter of the circle, you
have to solve for its radius. The radius of the circle is half its diameter. Therefore,
the radius of the circle is 5 (10/2).
Now, you substitute the measurements to the formula:
A = 3.14 (5)^2
A = 3.14 (25)
A = 78.5 sq. units
Answer:
x = 7
Step-by-step explanation:
Because this is a right triangle, one angle is a right angle (90°). All triangles have all three angle measures adding up to 180°, so the other two angles' measures add up to 90° (90 + 90 = 180).
Combine like terms of the angle measures.
6x + 9x = 15x
-3 + (-12) = -15
15x - 15
Because the sum of the measures of the two angles have to equal 90,
15x - 15 = 90
Add 15 from both sides.
15x = 105
Divide both sides by 15.
x = 7
To check, substitute 7 in both expressions.
6(7) - 3 = 39
9(7) - 12 = 51
39 + 51 + 90 (the measure of the right angle) = 180, so the value of x is 7.
I hope this helped :)
