Answer:
21 cm by 21 cm
Step-by-step explanation:
The formula for the area of a square is A = x^2, where x is the length of any one side of the square. Here,
441 cm² = x²
This actually has two roots: {√441, -√441), but since x must be positive here, to be a dimension of the square, we choose +√441, or +21.
The dimensions of the square are 21 cm by 21 cm.
Answer:
+9-12
==3
Step-by-step explanation:
when u multiply - and + it will always be -
Answer:
the question is incomplete, so I looked for a similar one:
<em>After the release of radioactive material into the atmosphere from a nuclear power plant, the hay was contaminated by iodine 131 ( half-life, 8 days). If it is all right to feed the hay to cows when 10% of the iodine 131 remains, how long did the farmers need to wait to use this hay? </em>
iodine's half life (we are given x, we need to find b):
0.5A₀ = A₀eᵇˣ
x = 8 days
we eliminate A₀ from both sides
0.5 = eᵇ⁸
ln 0.5 = ln eᵇ⁸
-0.69315 = b8
b = -0.69315 / 8 = -0.08664
since the farmers need to wait until only 10% of the iodine remains (we already calculated b, now we need to find x):
0.1A₀ = A₀eᵇˣ
0.1 = eᵇˣ
ln 0.1 = bx
where b = -0.08664
x = ln 0.1 / -0.08664 = -2.302585 / -0.08664 = 26.58 days
1 pound = 16 ounces
If you have 6 pounds of horsehair,
16 ounces × 6 pounds = 96 ounces
One pull weights about 0.011 ounces, in order to find how many pulls you can make with 96 ounces of horsehair, you divide 96 ÷ 0.011 .
96 ÷ 0.011 = 8727 (rounded to whole number)
8727 pulls could be made from 6 pounds of horsehair.
Answer:
224
Step-by-step explanation:
Hello!
To find f(-7) you simply plug the value, -7, into the function.
This will get you:
f(-7) = 4(-7)^2 - 4(-7)
Remember that the square of a negative number is a positive! Also, remember to use the order of operations (PEMDAS)!
This will get you:
f(-7) = 4(49) - 4(-7)
f(-7) = 196 - (-28)
f(-7) = 224
Hope this helps!