20.50 * 0.8 = $16.40
16.40 * 0.4 = $6.56
Final selling price = $6.56
Answer:
b=20 yards
Step-by-step explanation:
15^2+x^2=25^2
225+x^2=625
x^2=400
x=20
Divide 84.87 by 1.15, and you get 73.8
Then you can check your work by multiplying 73.8 by 1.15 and you get 84.87
Answer:
y = 5, -4
Step-by-step explanation:
To solve proportions you cross-multiply.

Now that we have 8 = y^2 - y - 12, we must make the entire trinomial equal to 0 by subtracting 8 from both sides.
y^2 - y - 20 = 0
Factor the trinomial.
(y - 5)(y + 4) = 0
Make both factors equal to 0 to solve for both values of y.
- y - 5 = 0 --> y = 5
- y + 4 = 0 --> y = -4
y = 5, -4
I think it’s 84 you multiply 14 and 12 then divide by 2 since it is a triangular prism