If the 2 base angles are congruent then the two opposite sides are congruent
Answer:
(17 , -18)
Step-by-step explanation:
5 = (-7 + x) / 2
x = 17
-8 = (2 + y) / 2
y = -18
Answer:
P = 24
A ≈ 41.6
Step-by-step explanation:
The polygon is a regular hexagon, so the triangle shown is a 30-60-90 triangle. So the short leg of the triangle is 2, which makes the side length of the hexagon 4.
That means the perimeter is P = 4 × 6 = 24.
The area of a regular polygon is:
A = ½ aP
where a is the apothem and P is the perimeter.
A = ½ (2√3) (24)
A = 24√3
A ≈ 41.6
Let's say the item starts off at $100.
A 55% decrease means 100%-55% = 45% of the value is still there. The item is now worth 0.45*100 = 45 dollars.
Now increase this by 25%. The long way to do this is to add 25% of 45 onto 45
(25% of 45) + (45) = 0.25*45+45 = 11.25+45 = 56.25
Or, we can multiply 45 by 1.25 since the multiplier 1.25 represents a 25% increase
1.25*45 = 56.25
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The item was $100, it drops to $45 after the 55% decrease, then it is $56.25 after the 25% increase.
Let's compute the percent difference
A = 100 = old value
B = 56.25 = new value
C = percent difference
C = 100*(B-A)/A
C = 100*(56.25-100)/100
C = -43.75%
The negative C value indicates a percent decrease.
So combining a 55% decrease and a 25% increase leads to an overall decrease of 43.75%
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A shortcut is to multiply 0.45 and 1.25 to get 0.5625
Then subtract this from 1 to get 1-0.5625 = 0.4375
This is another way to see we have a 43.75% decrease.
Answer:
a = 3
b = 2
c = 0
d = -4
Step-by-step explanation:
Form 4 equations and solve simultaneously
28 = a(2)³ + b(2)² + c(2) + d
28 = 8a + 4b + 2c + d (1)
-5 = -a + b - c + d (2)
220 = 64a + 16b + 4c + d (3)
-20 = -8a + 4b - 2c + d (4)
(1) + (4)
28 = 8a + 4b + 2c + d
-20 = -8a + 4b - 2c + d
8 = 8b + 2d
d = 4 - 4b
Equation (2)
c = -a + b + d + 5
c = -a + b + 4 - 4b+ 5
c = -a - 3b + 9
28 = 8a + 4b + 2c + d (1)
28 = 8a + 4b + 2(-a - 3b + 9) + 4 - 4b
28 = 6a - 6b + 22
6a - 6b = 6
a - b = 1
a = b + 1
220 = 64a + 16b + 4c + d (3)
220 = 64(b + 1) + 16b + 4(-b - 1 - 3b + 9) + 4 - 4b
220 = 60b + 100
60b = 120
b = 2
a = 2 + 1
a = 3
c = -3 - 3(2) + 9
c = 0
d = 4 - 4(2)
d = -4
