A and 90-a is the measure of the two angles
a=90-a-6
2a=84
a=42
42° and 48°
It increased by $3.15
The new monthly cost is $48.15
Answer: A. divided the difference of the two quantities by the sum of the two quantities.
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Explanation:
The difference of the quantities is 20-15 = 5
The sum of the quantities is 20+15 = 35
Dividing those results leads to 5/35 = 0.142857 which rounds to 0.1429
That converts to 14.29%
This is likely the path Adam took. This path is incorrect. The correct steps are shown below
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Difference = 20-15 = 5
Divide the difference over the original quantity
5/20 = 1/4 = 0.25 = 25%
We have a 25% decrease because the new quantity (15) is smaller than the old quantity (20)
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Here's another way to approach the problem
A = old value = 20
B = new value = 15
C = percent change
C = [ (B-A)/A ] * 100%
C = [ (15-20)/20 ] * 100%
C = (-5/20)*100%
C = -0.25*100%
C = -25%
The negative C value means we have a negative percent change, ie we have a percent decrease. So this is another way to get a 25% decrease.
The solution of the equation x2+7x is 0, -7 using the quadratic formula.
Step-by-step explanation:
x2 + 7x = 0
-b ± √
b2 - 4(ac)/ 2a
substitution,
a = 1, b = 7, c = 0
= -7 ± √(7)2 - 4(1 x 0) / 2 x 1
= - 7
± 7 / 2
x = 0 , -7
The answer to 134.42 by 28 is estimated to 4.8
