How do you use the quadratic formula to solve $2.5x^2-3.3x=1.2x-1.5$ ?

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Answer 1 · 2017-09-10T11:04:43

Solution: $x ~~ 1.36, x ~~ 0.44$

$2.5x^2-3.3x=1.2x-1.5 or 2.5x^2-3.3x -1.2x+1.5 =0$ or

$2.5x^2-4.5x+1.5 =0$ Comparing with standard quadratic

equation $ax^2+bx+c=0$ we get here,

$a= 2.5 , b= -4.5 ,c =1.5$ . Discriminant $D=b^2-4ac$ or

$D = -4.5^2 - 4*2.5*1.5 = 5.25$

$x= (-b +- sqrtD)/(2a) = (4.5 +- sqrt5.25)/(2*2.5)$ or

$x= (4.5 +- sqrt5.25)/5 or x ~~0.9+- 2.29/5$ or

$x ~~0.9+- 2.29/5 or x ~~ 0.9+- 0.46$ or

$x ~~ 1.36 (2dp), x ~~ 0.44 (2dp)$ [Ans]

How do you use the quadratic formula to solve 2.5x^2-3.3x=1.2x-1.52.5x^2-3.3x=1.2x-1.5?