You have posted 2 separate questions here. Please, next time, separate them with a blank line:
<span>A circle has an area of 81 3.14 units . what is the diameter in terms of 3.14?
I'd prefer you write this as
"</span><span>A circle has an area of 81 pi units . what is the diameter in terms of pi?
Area of a circle = A = pi*r^2. Note that r= diameter / 2. Here, the area is 81 pi square units, or 9^2 * pi square units, which means that the radius is 9 units. The diameter is then 2(9 units) = 18 units.
Your second question, separated from the first, is:
"</span><span>a circle has an area of 81 Pi square units what is the diameter of the circle?"
</span><span>
Use the following formula or formulas: d = 2*r; A = pi*r^2; A = pi*(d/2)^2. Find r first, and then find d.
</span>
Well if you're wanting to use substitution, you first have to end up with one term on either side of the equation. Use the second one as it's easiest.
So: x-2y=11, so find -2y as there is a -2y in the first equation.
then that becomes -2y=11-x. then sub that into equation 1, and you get:
-x+11-x=-13, which equals to -2x+11=-13, which is -2x=-24, so therefore
x=12. then chuck the x into any of the equations to find what y equals.
hope this helps!
Answer:
19.5959179423
Step-by-step explanation:
Answer:
y = 3x - 23
Step-by-step explanation:
y + 4 = 3(x - 9)
y + 4 = 3x - 27
y = 3x - 23
There are 27 & 1/3 pencils in each box. Each student will get 3 pencils per year. There will be 16 pencils left over.