alleryFor −2x²+3x+2=0, which quadratic-formula substitution is valid?
A(−3±√25)/(−2)
B(−3±√7)/(−4)
C(−3±√25)/(−4)
D(3±√25)/(−4)
Answer & Solution
Correct answer: C. (−3±√25)/(−4)
Here a=−2,b=3,c=2, giving −b=−3, discriminant 25 and denominator −4.
Keep practising Quadratic Equations
Browse all Quadratic Equations questions for ICSE Class 10, or explore more Mathematics topics.
Related questions
Match each relation between roots α, β of ax² + bx + c = 0 with its formula:Match each geometric word problem with its quadratic equation model:Match each quadratic equation with its roots:Match each quadratic discriminant D = b² - 4ac value with the nature of roots:₹1,000 becomes ₹1,210 after 2 years, compounded annually at a constant nonnegative rate. ATwo ages differ by 24 years; in 4 years their product is 432. Younger age now x. Equation?How many rectangles have perimeter 20 m and area 30 m²?A maker produces n toys, n<20. Each costs ₹(40−n); total cost ₹375. Find n.