Question

What is the value of x2+3x-7 when x = -4?

Answer 1

Answer:

$\huge{ \fbox{ \sf{ - 3}}}$

Step-by-step explanation:

$\underline{ \text{Given}} :$

$\longrightarrow{ \sf{ \: x = - 4}}$

$\underline{ \text{To \: find}} : \: \sf{Value \: of \: the \: given \: expression}$

$\sf{ {x}^{2} + 3x - 7}$

$\text{Step \: 1}$ : Plug the value of x

$\sf{ { \mapsto ( - 4)}^{2} + 3 * \: ( - 4) \: - 7}$

$\text{Step \: 2}$ : Evaluate the power

$\underline{ \text{Remember!}}$ : Multiplying a negative integer by a negative integers gives a positive integer.

$\mapsto{ \sf{16 + 3 \: * \: ( - 4) - 7}}$

$\text{Step \: 3}$ : Multiply : 3 by -4

$\underline{ \sf{Remember!}}$ : Multiplying positive integer by any negative integer gives a negative integer.

$\mapsto{ \sf{16 + ( - 12) - 7}}$

$\underline{ \text{Remember!}}$ : ( + ) * ( - ) = ( - )

$\mapsto{ \sf{16 - 12 - 7}}$

$\text{Step \: 4}$ : Subtract 12 from 16

$\mapsto{ \sf{4 - 7}}$

$\text{Step \: 5}$ : Subtract 7 from 4

$\underline{ \text{Remember!}}$ : The negative and positive integers are always subtracted but posses the sign of the bigger integer.

$\mapsto{ \boxed{ \sf{ - 3}}}$

Remember to follow PEMDAS

Parentheses , Exponents , Multiplication , Division , Addition , Subtraction

Hope I helped!

Best regards! :D

~$\text{TheAnimeGirl}$