complete the square -x^2+7x-13

Question

solomonzelman · Answer

$$-x^2+7x-13=0$$

solomonzelman · Answer

1) multiply everything times -1.
2)  (since 7=3.5 * 2  and 3.5^2=12.25 )  subtract .75 from both sides

If you haven't learned about imaginary numbers, than say no solution.

anonymous · Answer

Divided both sides by negative 1 to get

X^2-7x+13=0
X^2-7x+42.25+13=42.25
X^2-7x+55.25=42.25
?????????

solomonzelman · Answer

No, lightning
$$-x^{2}+7x-13=0$$$$x^{2}-7x+13=0$$$$x^{2}-7x+13-0.75=0-0.75$$$$x^{2}-7x+12.25=-.75$$$$(x-3.5)^{2}=-.75$$

the solutions will be imaginary.

solomonzelman · Answer

@ashleylk5 , which course is this? Algebra 1?
In your class, have you learned about imaginary numbers, or about i that is equal to √-1 ?

anonymous · Answer

Thanks you guys ^^

solomonzelman · Answer

You welcome:)  Do you need more help ? reply if you do...

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