Write Quadratic Equation: Write down the quadratic equation.We have the quadratic equation 5x2+70x+245=0.
Factor Out GCF: Factor out the greatest common factor (GCF) if possible.In this case, we can factor out 5 from each term.5(x2+14x+49)=0
Set Equation Equal to Zero: Set the factored equation equal to zero and solve for x.Now we have a simpler quadratic equation: x2+14x+49=0.We need to find two numbers that multiply to 49 and add up to 14.
Factor the Quadratic Equation: Factor the quadratic equation.The numbers that multiply to 49 and add up to 14 are 7 and 7.So we can write the equation as (x+7)(x+7)=0, which is also (x+7)2=0.
Solve for x: Solve for x.Since (x+7)2=0, we can take the square root of both sides to get x+7=0.Subtracting 7 from both sides gives us x=−7.
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