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Which of the following are solutions to the equation below?Check all that apply.x2 – 6x + 40 = 6x + 5

a. -5 b. -6 c. 7 d. 5 e. 6

User Moorecats
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2 Answers

4 votes
x^2 - 6x + 40 = 6x + 5

x^2 - 6x + 40 -6x - 5 = 0 (move all terms to one side)

x^2 - 12x + 35 = 0

(x - 7)(x - 5) = 0

x = 7, 5

hope that helps, God bless!
User Geralde
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8.5k points
7 votes

Answer:

c.7 and d.5

Explanation:

Given the following equation :


x^(2)-6x+40=6x+5

This equation is equivalent to the following equation :


x^(2)-6x+40=6x+5


x^(2)-6x+40-6x-5=0


x^(2)-12x+35=0

Given an equation
ax^(2)+bx+c=0 we can find the solutions using the quadratic equation (x1 and x2 are the solutions) :


x1=\frac{-b+\sqrt{b^(2)-4ac}}{2a}


x2=\frac{-b-\sqrt{b^(2)-4ac}}{2a}

Using this equations :


x^(2)-12x+35=0


a=1\\b=-12\\c=35


x1=\frac{-(-12)+\sqrt{(-12)^(2)-4.(1).(35)}}{2.(1)}=7


x2=\frac{-(-12)-\sqrt{(-12)^(2)-4.(1).(35)}}{2.(1)}=5

Given the two solutions x1 and x2 we can write the equation :


ax^(2)+bx+c=0
a.(x-x1).(x-x2)=0


x^(2)-12x+35=0 is equivalent to


(x-7).(x-5)=0

The solutions for this equation are 7 and 5.

Therefore, c.7 and d.5 are the solutions for this exercise.

User Bartosz
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8.0k points