Question

The solution for $2x^2-9x+7=0$ is

• A. $2,3$
• B. $1,\frac{9}{4}$
• C. $\frac{1}{4},\frac{13}{4}$
• D. $1,\frac{13}{4}$

Answer 1

The correct option is D $1,\frac{13}{4}$

Given Quadratic equation is

$2x^2-9x+7=0$
Comparing it with the general form of quadratic equation $a{x}^2+bx+c=0$

we write, $a=2,b=-9,c=7$

Quadratic formula is $x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}$

$⟹x=\frac{-(-9)\pm \sqrt{(-9{)}^2-4(2\left)\right(7)}}{2\left(2\right)}$

$⟹x=\frac{9\pm \sqrt{81-56}}{4}$

$⟹x=\frac{9\pm \sqrt{25}}{4}$

$⟹x=\frac{9\pm 5}{4}$

$⟹x=\frac{9+5}{4}x=\frac{9-5}{4}$

$⟹x=1,\frac{7}{2}$