Question

What is the discriminant of the polynomial?
2x^2+5x-8
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Answer 1

`▪▪▪▪▪▪▪▪▪▪▪▪▪  {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪`

Let's find the discriminant (D) of the given polynomial ~

Let's compare the given quadratic expression with general expression ~

`\boxed{ \boxed{ \sf {ax}^(2) +b x + c }}`

we get ;

• 
  `\sf \: a = 2`
• 
  `\sf \: b = 5`
• 
  `\sf \: c = - 8`

Now, use the following formula :

`\qquad \sf \dashrightarrow \: D = b² - 4ac`

`\qquad \sf \dashrightarrow \: D = (5) {}^(2) - (4 * 2 * ( - 8))`

`\qquad \sf \dashrightarrow \: D = 25 - ( - 64)`

`\qquad \sf \dashrightarrow \: D = 25 + 64`

`\qquad \sf \dashrightarrow \: D = 89`

Therefore, discriminant of the given quadratic expression is 89