24x^2 - 45x - 21 = 0

[tex]24x^2-45x-21=0\\
3(8x^2-15x-7)=0\\
8x^2-15x-7=0\\
\Delta=(-15)^2-4\cdot8\cdot(-7)=225+224=449\\
\sqrt{\Delta}=\sqrt{449}\\
x_1=\dfrac{-(-15)-\sqrt{449}}{2\cdot8}=\dfrac{15-\sqrt{449}}{16}\\
x_2=\dfrac{-(-15)+\sqrt{449}}{2\cdot8}=\dfrac{15+\sqrt{449}}{16}[/tex]

[tex]24x^2-45x-21=0

3(8x^2-15x-7)=0 /:3

8x^2-15x-7=0

a=8... b=-15.... c=-7

delta= b^2-4ac=449

x_1= \frac{15- \sqrt{449} }{16}

x_2= \frac{15+ \sqrt{449} }{16}




[/tex]√ΔΔΔΔΔΔΔΔΔ