1. Answer: D. <span>A = 100 (1/2)^t/13.27
</span>Exponent equation formula would be an= a0( 1+r)^t
In this question, the radio isotopes will become half of its weight after the half-life. So, the ratio would be -0.5 (r= -0.5)
The halftime is 13.27 hours, so the time will be divided by that number. The result would look like this:
an= a0( 1+r)^t
an= a0( 1-0.5)^t/13.27
an= a0( 1/2)^t/13.27
2. Answer: x= 74°
<span>The ladder and the building will make a right triangle with the ladder as the hypotenuse.
The foot of the ladder is 2 feet from the building, so the adjacent side is 2ft.
It reaches a point 7 feet high on the building, so the opposite side is 7ft</span>
You can find the angle by using the tan equation
tan x= opposite / adjacent
tan x= 7/2= 3.5
x= 74°
This problem cannot be factored
The answer is x² + 23x + 49
The area (A) of the shaded region is the difference between the area of the rectangle (A1) and the white square (A2).
A = A1 - A2
A1 = (x + 10)(2x + 5)
= 2x² + 5x + 20x + 50
= 2x² + 25x + 50
A2 = (x +1 )² = x² + 2x + 1
A = A1 - A2
= 2x² + 25x + 50 - (x² + 2x + 1)
= 2x² + 25x + 50 - x² - 2x - 1
= x² + 23x + 49
Ok so I think it’s B. Let me go get a piece of paper and verify that for you.
5 + 5 + 5 + 5 + 5 + 5 = 30 (6 bills)
1 + 1 + 1 + 1 + 1 = 5 (5 bills)
30 + 5 = 35 (11 bills)
