Answer:
-21.5
Step-by-step explanation:
The correct solution is 75.
The surface area is 47.1 sq in.
Step-by-step explanation:
Given,
The height (h) of the coin (cylinder shaped) = 5 inches
The radius (r) = 1.5 inches
To find the surface area of the coin.
We need to find the lateral surface area of the coin.
Formula
The surface area of the coin of radius r and height h is 2πrh.
Now,
Putting the value of h and r and π=3.14 we get,
Area = 2×3.14×1.5×5 sq inches
= 47.1 sq in
Hence, the surface area is 47.1 sq in.
Louise’s answer is not correct. She is missing the term 30x3. When squaring a binomial, it is best to write the product of the binomial times itself. Then you can use the distributive property to multiply each term in the first binomial by each term in the second binomial. Louise also could have used the formula for a perfect square trinomial, which is found by squaring a binomial.
