Question

What would be the answer to this question

Answer 1

this is the answer for this question, you can follow this step. The final one I use the calculat

Answer 2

Explanation:

`√(28 - 6x) = x - 6 \\ ({ √(28 - 6x)) }^(2) = {(x - 6)}^(2) \\ + - (28 - 6x) = {x}^(2) - 12x + 36 \\ 0 = {x}^(2) - 6x + 8 \\ 0 = (x - 2)(x - 4) \\ x - 2 = 0 \\ x - 4 = 0 \\ x = 2 \\ x = 4 \\ we \: must \: check \: the \: answer \: \\ √(28 - 6(2)) = 2 - 6 \\ √(16) = - 4 \\ 4 = - 4 \\ it \: is \: wrong. \: \\ √(28 - 6(4)) = 4 - 6 \\ √(4) = - 2 \\ 2 = - 2 \\ it \: is \: wrong \: too.`

-( 28 - 6x ) = x² - 12x + 36

x² - 18x + 64 = 0

√∆ = √( 324 -256)= √68 = 2√17

x = (18 ± 2√17)/2 = 9 ± √17 → 9+√17 ✓

9-√17 is not acceptable because the radical answer can not be negative.