Step-by-step explanation:
The ratio of the two shorter legs of the top triangle is

The bottom triangle has the following ratio:

Since their ratios are the same, this means that the two triangles are similar.
area=legnth times width
we notice this is a special case
(a+b)(a-b)=a^2-b^2
area=(a+3b)(a-3b)=a^2-9b^2
area=a^2-9b^2
Answer: letter D. Most of the mass of an atom comes from elctron cloud
Step-by-step explanation: your welcome and have a good day
Answer:
B. (see attached)
Step-by-step explanation:
All the answers agree that the function is x² for x < 1. Where they disagree is in the slope and y-intercept of the linear portion for x > 1.
The line has a slope that is less than 1 unit of rise for 1 unit of run, so will not be selections A or C, which have slopes of 3.
The y-intercept is clearly positive if we extend the line to the left until it reaches the y-axis. This eliminates selection D from consideration, leaving only selection B.