A because (-5)^2 = 25 + 2(5) =35-1=34
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Equation
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y = -3x - 9
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Option 1
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If I substitute x = -9, I should get y = 0
When x = -9
y = -3 (-9) - 9
= 18 (I did not get 0, wrong)
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Option 2
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If I substitute x = -3, I should get y = 0
y = -3(-3) - 9
y = 9 - 9
y = 0 (Yes, I got 0, correct)
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Option 3
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If I substitute x = 0, I should get y = -3
y = -3 (0) - 9
y = 0 - 9
y = -9 (I did not get -3, wrong)
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Option 4
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If I substitute x = 0, I should get y = -9
y = -3 (0) - 9
y = 0 - 9
y = -9 (Yes, I got -9, correct)
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Answer: (-3, 0) and (0, 9) are ordered pairs of the equation (Answer B, D)
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Let the legs of the triangle be a and b, and the hypotenuse c.
Your first instinct might tell you to use the Pythagorean theorem to go about solving this because
. This works, but it is slow.
The fastest way to solve this is to recognize that the right triangle is a special triangle where the ratio of the sides are 3:4:5. This means that if the legs are 9 and 12, then the hypotenuse is 15 because 3*3 is 9, 3*4 is 12, and 3*5 is 15.
Given:
Triangle:
height = 6ft
base = 4ft
Rectangle:
length = x
Width = 6 ft
Surface Area = 150ft²
Area of a Triangle = h*b / 2 = (6ft * 4ft) / 2 = 12ft²
Area of a rectangle = Surface Area - Area of a Triangle
A = 150 ft² - 12 ft² = 138 ft²
138 ft² = x * 6ft
138 ft² / 6 ft = x
23 ft = x.
