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.
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The equations we get are
l = 6 + 2w (We get this from "The length of the rectangle is 6 more than 2 times the width.")
and
2l + 2w = 140 (We get this from the perimeter. Two times the length plus two times the width equals the perimeter of a quadrilateral.)
The first equation can be written as
l - 2w = 6
So now we have
2l + 2w = 140
l - 2w = 6
____________
Add the two equations.
We get 3l = 146
Divide by 3 on both sides.
l =
48
Your answer is
48
.
Answer:
-19ab + 2ab^2 +7
Step-by-step explanation:
all you do is combine the like terms. and the omly like terms are -10ab and -9ab. 2ab^2 is not one of the like terms simply because of that ^2.