Answer this multiple choice question correctly for 30 points and

Step-by-step explanation:

The total length of the space between rungs is the overall length less the width of 8 rungs, so is 206 -8(10). That space is divided into 7 equal parts, as shown by the equation in choice D.

_____

Choice A looks similar, but is not. In that equation, only the term 8(10) is divided by 7. You want the difference to be divided by 7, so must have a grouping symbol of some kind. Choice D uses the division bar to group the terms of the numerator. Parentheses would work, too, as in ...

  d = (206 -8(10))÷7

but without them, the equation is incorrect.

12cm

the answer is d

answer:   x = 3 + √11     and     x = 3 - √11

step-by-step explanation:

x² - 6x + 9 = 11

(x - 3)² = 11

x - 3 = ±√11

    x = 3 ± √11

x = 3 + √11     and     x = 3 - √11