In can be less mental effort if the equation is multiplied by -1 first.
.. x^2 -10x +8 = 0
.. x^2 -10x +25 +8 -25 = 0
.. (x -5)^2 = 17
.. x -5 = ±√17
.. x = 5 ±√17
The values of x that satisfy the given equation are
.. x = 5 -√17 ≈ 0.877
.. x = 5 +√17 ≈ 9.123
The answer is in the picture below
Steps to solve:
5x² = 15x
~Subtract 15x to both sides
5x² - 15x = 15x - 15x
~Simplify
5x² - 15x = 0
~Factor left side
5x(x - 3) = 0
~Factors equal 0
5x = 0 and x - 3 = 0
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~Simplify 5x = 0
5x/5 = 0/5
x = 0
~Simplify x - 3 = 0
x - 3 + 3 = 0 + 3
x = 3
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Thus, the correct answer is 0, 3.
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Best of Luck!
If the sum of two numbers is x
Then the equation is like this:
a+b = x
Then it says one of the number is 12. Change either a or b into 12
12 + b =x
If we want to find the other number, we need the make it into the subject
b = x - 12
Hope that help.