Question

24x^2 - 45x - 21 = 0

Answer 1

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

Answer 2

$24x^2-45x-21=0 3(8x^2-15x-7)=0 /:3 8x^2-15x-7=0 a=8... b=-15.... c=-7 delta= b^2-4ac=449 x_1= \frac{15- \sqrt{449} }{16} x_2= \frac{15+ \sqrt{449} }{16}$√ΔΔΔΔΔΔΔΔΔ