Answer: x = ¹/₂ ± √⁸¹
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2
Step-by-step explanation:
First write out the equation
x² - x - 20
Now we now write the equation by equating to 0
x² - x - 20 = 0
We now move 20 to the other side of the equation. So
x² - x = 20,
We now add to both side of the equation square of the half the coefficient of the (x) and not (x²) which is (1) . So, the equation now becomes
x² - x + ( ¹/₂ )² = 20 + ( ¹/₂ )²
x² - ( ¹/₂ )² = 20 + ¹/₄
( x - ¹/₂ )² = 20 + ¹/₄, we now resolve the right hand side expression into fraction
( x - ¹/₂ )² = ⁸¹/₄ when the LCM is made 4
Taking the square root of both side to remove the square,we now have
x - ¹/₂ = √⁸¹/₄
x - ¹/₂ = √⁸¹/₂
Therefore,
x = ¹/₂ ± √⁸¹
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2
Answer:
area = 1800 m²
Step-by-step explanation:
area of one triangle = 900 m²
if a parallelogram has the same height and base as the triangle, then that means the area or the two triangle and shaped as a parallelogram
is twice the area given.
area = 900 * 2
area = 1800 m²
Answer:
-88
Step-by-step explanation:
Let N(x) be the number of students at NMS for a certain number of years.
Let S(x) be the number of students at SMS for a certain number of years.
Let x be the number of years.
N(x)=1240-25x
S(x)=800-30x
When # of students is equal, N(x)=S(x). Therefore, we are looking for the value of x (# of years) when 1240-25x=800-30x
Subtract 1240 from each side
-25x=-440-30x
Add 30x
5x=-400
x=-88 years
Check your numbers.
Answer:
When x=4
P(x) =4 - 4(4)^2 + 4(4) -5
=4 - 4(16) + 16 -5
=4 - 64 +11
= -60 + 11
= -49
you would multiply speed by time
20 feet per second times 10 seconds = 200 feet total
