Question

Complete the square: x2+7x+?=(x+?)2

Answer 1

`{x}^(2) + 7x + (49)/(4) = {(x + (7)/(2)) }^(2)`

Step-by-step explanation:

`{x}^(2) + 7x + a = {(x + b)}^(2)`

`{x}^(2) + 7x + a = {x}^(2) + 2bx + {b}^(2)`

compare the x co-efficient

`7 = 2b`

`b = (7)/(2)`

compare the constants

`a = {b}^(2)`

`a = {( (7)/(2)) }^(2)`

`a = (49)/(4)`