Question

Use the FOIL method to evaluate the expression:

Answer 1

option b) 1 + 2√7

Step-by-step explanation:

Foil property method :-

`\red{ \boxed{ \orange{ \rm (a + b)(c + d) = ac + ad + bc + bd}}}`

then, on substituting the values,

`\sf⇒ \:  \: 8 + 4 √(7) - 2 √(7) - 7`

`\sf⇒ \:  \: \green{ \underline{\bold{ \red{1 + 2 √(7) }}}}`

Answer 2

`\sf b.) \ 1 +2√(7)`

Step-by-step explanation:

Foil method: (a + b)(c + d) = ac + ad + bc + bd

Solving steps:

`(4 - √(7) )(2 + √(7) )`

`(4)(2) + 4(√(7) ) + (-√(7) )(2) + (-√(7) )(√(7) )`

`8 + 4√(7) - 2√(7) - 7`

`8 -7 + 4√(7) - 2√(7)`

`1 +2√(7)`