Question

Using the quadratic formula to solve 7x2 – x = 7, what are the values of x? StartFraction 1 plus-or-minus StartRoot 195 EndRoot i Over 14 EndFraction StartFraction 1 plus-or-minus StartRoot 197 EndRoot Over 14 EndFraction StartFraction 1 plus-or-minus StartRoot 195 EndRoot Over 14 EndFraction StartFraction 1 plus-or-minus StartRoot 197 EndRoot i Over 14 EndFraction

Answer 1

B

Explanation:

Answer 2

`x=\frac{1(+/-)√(197)} {14}`

Explanation:

we know that

The formula to solve a quadratic equation of the form

`ax^(2) +bx+c=0`

is equal to

`x=\frac{-b(+/-)\sqrt{b^(2)-4ac}} {2a}`

in this problem we have

`7x^(2) -x=7`

equate to zero

`7x^(2) -x-7=0`

so

`a=7\\b=-1\\c=-7`

substitute in the formula

`x=\frac{-(-1)(+/-)\sqrt{-1^(2)-4(7)(-7)}} {2(7)}`

`x=\frac{1(+/-)√(197)} {14}`