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Xelga [282]
2 years ago
14

Zacharias is using the quadratic formula to solve the equation 0 = –2x2 + 5x – 3. He begins by substituting as shown. Quadratic

formula: x = StartFraction negative b plus or minus StartRoot b squared minus 4 a c EndRoot Over 2 a EndFraction Substitution: x = StartFraction negative 5 plus or minus StartRoot 5 squared minus 4(2)(negative 3) EndRoot Over 2(negative 2) EndFraction What error did Zacharias make? The –5 should be 5. The 52 should be –52. The 2 in the numerator should be –2. The 2 in the denominator should be –2
Mathematics
2 answers:
Xelga [282]2 years ago
8 0

Answer: d on edge2020

Step-by-step explanation: no cap

almond37 [142]2 years ago
7 0

Answer:

The 2 in the numerator should be –2

Step-by-step explanation:

we know that

The formula to solve a quadratic equation of the form

ax^{2} +bx+c=0

is equal to

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

in this problem we have

-2x^{2} +5x-3=0  

so

a=-2\\b=5\\c=-3

substitute in the formula

x=\frac{-(5)(+/-)\sqrt{5^{2}-4(-2)(-3)}} {2(-2)}

x=\frac{-5(+/-)\sqrt{25-24}} {-4}

x=\frac{-5(+/-)1} {-4}

x=\frac{-5(+)1} {-4}=1

x=\frac{-5(-)1} {-4}=1.5

therefore

The 2 in the numerator should be –2

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6 0
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A student scored in the 85th percentile on her chemistry exam. What does this student's score mean in relation to those of the o
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