(3x+7)(3x-7) if necessary combine like terms

Mathematics

1 answer:

34kurt3 years ago

3 0

Answer:

9x^2 -49

Step-by-step explanation:

We recognize that this is of the form

(a+b)(a-b) = a^2 - b^2

3x = a and 7 =b

(3x)^2 - 7^2

9x^2 -49

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Write an equation in point slope form for the line that passes through (-5,6) and (-3,-9).

Finger [1]

$\bf (\stackrel{x_1}{-5}~,~\stackrel{y_1}{6})\qquad
(\stackrel{x_2}{-3}~,~\stackrel{y_2}{-9})
\\\\\\
slope = m\implies
\cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{-9-6}{-3-(-5)}\implies \cfrac{-9-6}{-3+5}\implies -\cfrac{15}{2}$

$\bf \begin{array}{|c|ll}
\cline{1-1}
\textit{point-slope form}\\
\cline{1-1}
\\
y-y_1=m(x-x_1)
\\\\
\cline{1-1}
\end{array}\implies y-6=-\cfrac{15}{2}[x-(-5)]\implies y-6=-\cfrac{15}{2}(x+5)
\\\\\\
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