Question

I dont understand this, please give an explanation

Answer 1

`\huge \qquad \boxed{ \sf Aᥒsᥕᥱr ☂}`

let's plug in the value of x as -5, in the given expression ~

`\qquad\rightarrowtail \sf {x}^(2) + 5x - 4`

`\qquad\rightarrowtail \sf { (- 5)}^(2) + 5( - 5) - 4`

`\qquad\rightarrowtail \sf 25 - 25 + 4`

`\qquad\rightarrowtail \sf 4`

Therefore, we got the required value 4

Answer 2

`\bold\blue{x {}^(2) + 5x + 4}`

Here ,

we just need to substitute " x = - 5 " in the equation above.

`\bold{x {}^(2) + 5x + 4} \\\bold{ ( - 5) {}^(2) + 5( - 5) + 4} \\ \bold{ \cancel{25} - \cancel{25} + 4} \\ \fbox\pink{⇢ 4}`

hope helpful ~