Answer:
394.9 cm
Step-by-step explanation:
The formula for a cone's surface area is A = π r ( r + √r^2 + h^2 ).
r = radius
h = height
The Pythagorean theorem, a^2 + b^2 = c^2, will be needed to find the height.
Plug in the values.
a(unknown)^2 + 6^2 = 15^2
A + 36 = 255
255 - 36 = 189
√189 ≈ 13.7
Surface area formula, plug in the values.
A = 3.14 × 6 ( 6 + √6^2 + 13.7^2 )
*PEMDAS*
A = 3.14 × 6 ( 6 + √36 + 187.69 )
A = 3.14 × 6 ( 6 + √223.69 )
A = 3.14 × 6 ( 6 + 14.95 )
A = 3.14 × 6 ( 20.96 )
A = 3.14 × 125.76
A = 394.8864
*round to nearest tenth*
A = 394.9 cm
Hope this helps! :)
Answer:
B. Beth's age is 18 years, and Sally's age is 42 years.
Step-by-step explanation:
You can solve this question in a couple of different ways. First, you can use process of elimination. You know that Sally is older than Beth because she has to be 3 times older 6 years ago, so you can get rid of options C and D because they both show Beth as being older. Now you only have A and B, and you can use a different process. Now from just looking at it, you can tell that A actually already shows Sally as 3 times Beth's age, 15 * 3 = 45. If you go to B, you can go ahead and subtract 6 from 18 (Beth's age) which will give you 12, and then multiply that by 3 to get 36. Now if you take 42 (Sally's age) and subtract 6 from it as well, you will get 36. This means that is lines up. To simplify, you are subtracting 6 from both 18 and 42, and then you are multiplying the lower number by 3 to see if it gets to the bigger number.
Hope this helped ^-^
Answer:
14
Step-by-step explanation:
.28 times 50 equals 14
Answer:
The constant of proportionality is 2.
Step-by-step explanation:
In an equation for which we are looking for the constant of proportionality, we use the base form below.
y = kx
In which k is the constant of proportionality. If we use the equation given
y = 2x
We can see k = 2