Question 1183025
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 Students are trying to factor quadratic expressions using the guess-and-check method. 
Find the mistake in each student's work. Then give the correct answer.
a) x(small 2)―x―72=(x―8)(x+9)
b) 3x(small 2)―19x+28=(3x―4)(x―7)
c) 6x(small 2)+25x+4=(2x+1)(3x+4)
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            @MathLover1 misread the problem.


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The task &nbsp;<U>IS &nbsp;NOT</U> &nbsp;to check multiplications of binomials.


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The task is to check if the DECOMPOSITION/factoring is made correctly.



<pre>
(a)  x^2 - x - 72 = (x+8)*(x-9)



(b)  3x^2 - 19 + 28 = (3x-7)*(x-4)



(c)  6x^2 + 25x + 4 = (6x+1)*(x+4)
</pre>


So, for your safety, you better ignore the post by @MathLover1.