Answer:
Option C 
Step-by-step explanation:
we know that
the surface area of a pyramid is equal to
where
B is the area of the base
LA is the lateral area
The area of the base B is
The lateral area is equal to
the surface area is equal to
Answer:
E-F and E-D
C-B and C-D
Step-by-step explanation:
The circle and triangle are as shown. The options are:
- A-B and C-B
- E-F and E-D
- E-D and C-D
- A-F and E-F
- C-B and C-D
By drawing radius lines from the center of the circle to the tangent points B, D, and F, we can divide the triangle into 3 kites. Therefore, only segments that are legs of the same kite are congruent. So the answer must be E-F and E-D, and C-B and C-D.
C) (0.85 + x/100)(250+145) does not give the correct answer.
Explanation
A) works; adding the two costs together is 250+145=395. We multiply this by 0.85 because 100%-15%=85%=0.85. We also have x% tax, which is represented by x/100, added to 100% of the value, or 1.00. Altogether this gives us
395(0.85)(1+x/100) = 395(0.85 + (0.85x/100)) = 395(0.85) + 395(0.85x/100)
= 395(0.85) + 395(0.0085x)
B) works; we have 250+145 for the original price; we have 85% = 0.85 of the value; we also have 100% + x%, which is (100+x)/100.
C) does not work; (0.85+x/100)(395) does not take into consideration that you are finding the tax after taking the 85%. This will simplify out to
0.85*395 + (x/100)(395) = 335.75 + 395x/100 = 335.75 + 3.95x, which is too much.
D) works; simplifying the expression from A, we have 395(0.85) + 395(0.0085x) = 335.75 + 3.3575x.
The number of observations is 15
