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What are the approximate solutions of 2x2 + 9x = 8 to the nearest hundredth?

Ax ≈ 1.22 and x ≈ 3.28
Bx ≈ −0.76 and x ≈ 5.26
Cx ≈ −1.22 and x ≈ −3.28
Dx ≈ −5.26 and x ≈ 0.76

Verified Answer :

Answer:

The roots of the equations are x ≈ -5.26 and x ≈ 0.76 .

Option (d) is correct.

Step-by-step explanation:

Formula for the roots is given by .

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

As the equation in the form

\(2x^{2} + 9x - 8 = 0\)

As the equation in the form ax² + bx + c = 0

a = 2, b= 9 , c = -8

Put in the formula

\(x = \frac{-9 \pm \sqrt{9^{2} -4\times 2\times -8}}{2\times 2}\)

\(x = \frac{-9 \pm \sqrt{81 + 64}}{4}\)

\(x = \frac{-9 \pm \sqrt{145}}{4}\)

\(\sqrt{145} = 12.04\)

Thus First roots be

\(x = \frac{-9 - 12.04}{4}\)

\(x = \frac{-21.04}{4}\)

x ≈ -5.26

The second root be

\(x = \frac{-9 + 12.04}{4}\)

\(x = \frac{3.04}{4}\)

x ≈ 0.76

Therefore the roots of the equations are x ≈ -5.26 and x ≈ 0.76 .

Option (d) is correct.




Answer:

the anwser is d, hope this helps