Question

E REAL NUMBERS Evaluating a quadratic expression Evaluate the expression when c = -4. c² +5c+7

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Answer 1

→ 3

Explanation:

In this question wa are provided with an quadratic expression that is c² + 5c + 7 . And we are asked to find the value of given expression when c is equal to -4.

Solution:-

`\longmapsto \: \: \: \sf{c {}^(2) + 5c + 7}`

Substituting value of c as -4 :

`\longmapsto \: \: \: \sf{ { - 4}^(2) + 5( - 4) + 7}`

Simplifying ,

`\longmapsto \: \: \: \sf{16 - 20+ 7}`

`\longmapsto \: \: \: \sf{ - 4 + 7}`

We get ,

`\longmapsto \: \: \: \underline{ \boxed{ \sf{ \bold{3}}}}`

• Henceforth , the value of given expression when c is equal to -4 is "3"

Answer 2

• c² + 5c + 7 = 3.

Explanation:

Given expression: c² + 5x + 7.

We have to evaluate the given expression when c = -4.

To evaluate we can substitute the value of c as -4 in the given expression.

Substituting the value of c, we have

c² + 5c + 7

`\implies \sf (-4)^2 + 5(-4) + 7`

`\implies \sf 16 + (-20) + 7`

`\implies \sf 16 - 20 + 7`

`\implies \sf -4 + 7`

`\implies \sf 3`

Hence, when c = -4 then c² + 5c + 7 is 3.