Question

Solve the equation 6x^2 + 15x + 3= 2x^2 to the nearest tenth.

Answer 1

Answer:

x = -0.2 and x = -3.5

Step-by-step explanation:

Combine like terms in the given equation, by subtracting 2x^2 from both sides:

6x^2 + 15x + 3 = 2x^2

-2x^2                = -2x^2

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4x^2 + 15x + 3 = 0

This is a quadratic equation.  We'll find the two solutions using the quadratic equation

      -b ± √(b^2 - 4ac)

x = ---------------------------

                  2a

Here the coefficients of the quadratic are a = 4, b = 15 and c = 3.

Thus, the discriminant b^2 - 4ac is 15^2 - 4(4)(3), or +177

and from that we know we'll find two real, unequal roots.

                                -15 ± √177

The roots are:  x = ------------------- , or x = -0.2 and x = -3.5

                                         8