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Solve for x: 3x┬▓ - 7x + 2 = 0.
2,1/3
1,2/3
2,тИТ1/3
3,1/2
2,1/3
Use the product and sum rule: find two numbers that multiply to aimesc=6 and add to b=тИТ7. These are тИТ6 and тИТ1. Divide these by the leading coefficient 3 and change the sign to get the roots: 6/3=2 and 1/3.
A quadratic equation 3x2тИТ7x+2=0 is provided where coefficients are a=3,b=тИТ7,c=2.
x=2aтИТb┬▒b2тИТ4acтАЛтАЛ
Use the product and sum rule: find two numbers that multiply to aimesc=6 and add to b=тИТ7. These are тИТ6 and тИТ1. Divide these by the leading coefficient 3 and change the sign to get the roots: 6/3=2 and 1/3.
A frequent mistake is to neglect the negative sign on b when substituting into the quadratic formula or failing to divide by 2a at the end of the splitting method.
Identify coefficients
From the quadratic equation 3x2тИТ7x+2=0, identify the coefficients a=3, b=тИТ7, and c=2.
a=3,b=тИТ7,c=2
Apply Middle Term Splitting
Split the middle term тИТ7x into тИТ6x and тИТ1x such that their product is 3imes2=6.
3x2тИТ6xтИТx+2=0
Factorize by grouping
Group the terms and factor out common components: 3x(xтИТ2)тИТ1(xтИТ2)=0, which simplifies to (3xтИТ1)(xтИТ2)=0.
(3xтИТ1)(xтИТ2)=0
Solve for x
Set each factor to zero to find the roots: 3xтИТ1=0тЯ╣x=1/3 and xтИТ2=0тЯ╣x=2.
x=2,x=31тАЛ
A is correct because the factors of the equation yield the roots x=2 and x=1/3.
This method of finding roots is the foundation for solving higher-degree polynomials and finding the vertex of a parabola in coordinate geometry.