x ^2 -20x=-96=? solve it
Answers
x = 12 or 8
We have equation :-
x² - 20x = -96
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- 1st Method
[Splitting the middle term]
x² - 20x = -96
⇒ x² - 20x + 96 = 0
⇒ x² -12x -8x + 96 = 0
⇒ x(x - 12) -8(x - 12) = 0
⇒ (x - 12) (x - 8) = 0
So,
x can be 12 or 8 .
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- 2nd Method
[Quadratic formula]
x² - 20x + 96 = 0
Where,
a = 1
b = -20
c = 96
___________________[Put Values]
D = (-20)² - 4(1)(96)
D = 400 - 384
D = 16
√D = 4
Now to find zeroes we have a formula :-
______________[Put values]
x = {-(-20) ± 4} / 2
x = (20 ± 4)/2
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Case 1
x = (20 + 4)/2
x = 24/2
x = 12
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Case 2
x = (20 - 4)/2
x = 16/2
x = 8
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SOLUTION:-
Given:
x² - 20x = -96
So,
We can find through the middle splitting term method:
⚫When splitting the middle term, our objective is to write quadratic expressions as the product of two linear polynomials.
Now, we have;
x² - 20x + 96= 0
=) x² -12x -8x + 96 =0
=) x(x-12) - 8(x-12) =0
=) (x-12)(x-8) =0
Solve:
x-12= 0
=) x= 12
Solve:
x -8 = 0
=) x= 8
Hence,
The value is 12 & 8.