Question 309113
Given: {{{7D^2 + 50D + 7}}}
Set the equation equal to 0.
Then use the quadratic equation
*[invoke quadratic "D",7,50,7]
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The other way is to unfoil the equation
{{{7D^2 + 50D + 7 = 0}}}
Find the factors of 7: 1,7
Use the factors of 7 & 1 with the coefficient of the D^2 to get 50
7*7 + 1 = 50
Rewrite the equation
{{{(7D + 1)*(D + 7)}}}
Set each factor to 0 and solve for D
{{{7D + 1 = 0}}}
{{{7D = -1}}}
{{{highlight(D = -1/7)}}}
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{{{D + 7 = 0}}}
{{{highlight_green(D = -7)}}}