The sum of twice the square of a number and 7 times the number equals 15. What is the number? 1.1/2 2.3/4 3.3/2 4.5/3

1 Answer

Answer :

Answer-3 (3/2)

Explanation:-2x^2 + 7x = 15

2x^2 + 7x – 15 = 0

2x^2 + 10x-3x – 15 = 0

2x(x+5)-3(x+5) = 0

(x+5)(2x-3) = 0

x = -5 or x = 3/2

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