Need help asap... thanks!

90

Step-by-step explanation:

We know that area of ∆BCD = half of the area of rectangle BEFD, since any triangle drawn from taking a side and base and a point on the opposite side as the 3rd vertex has the half area of the rectangle

so, area of ∆BCD = 15×12/2 = 90 (since two legs of the right triangle are 15 and 12)

since area ∆BCD is half the area rectangle BEFD and sum of the area of ∆BEC and ∆CFD will be the rest of the area of rectangle BEFD, which is 90

The graph has an initial value of 60, and each successive term is determined by multiplying by One-third.

Step-by-step explanation:

Which is the best description of the graph of the function f(x) = 60(One-third)x?

A. The graph has an initial value of 20, and each successive term is determined by subtracting One-third.

B. The graph has an initial value of 20, and each successive term is determined by multiplying by One-third.

C. The graph has an initial value of 60, and each successive term is determined by subtracting One-third.

D. The graph has an initial value of 60, and each successive term is determined by multiplying by One-third.

Given:

f(x) = 60 (1/3)^x         see graph attached.

Examining the graph, we notice that

1. The graph has an initial value of 60, at point (0,60)

2. The graph decreases as x increases.  Each successive term is determined by multiplying by 1/3, namely in the sequence

{(0,60), (1,20), (2, 20/3), (3, 20/9), ...}

This means the choice is D (or the fourth one).