The correct answer is A.) { - 0.79 ; 1.08 }, because
<span><span> <span>For </span><span>ax^2 + bx + c = 0</span><span>, the value of </span>x<span> is given by:</span></span> <span> ;
a = - 7 ; b = 2 ; c = 6 ;
b^2 - 4ac = 4 + 168 = 172 ; </span></span>

≈ 13.11 ;<span><span>
x 1 = ( - 2 + 13.11 ) / (- 14) = 11.11 / ( - 14 ) </span></span>≈<span><span> -0.79 ;
x = 2 = ( - 2 - 13.11 ) / ( - 14 ) = (-15.11) / (- 14 ) </span></span>≈ 1.08 ;<span><span>
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Answer:
price for senior citizen is $11
price for child ticket is $8
7ft = 84in 84 ÷ 15 = 5.6 pieces he can cut from each board. Since .6 is not a whole piece measuring 15 inches long, he can only cut 5 pieces from each board.
So, 5 x 2 = 10
He would be able to cut 10 pieces measuring 15 inches long.
Hope this helps :)