The product of two consecutive integers is 342. Which quadratic equation can be used to find x, the greater number?
Since the greater number has value x, the smaller number must be (x-1). (x)(x-1)=342 (product of two consecutive integers) x^2 - x = 342 (expand brackets)
\[x^2 - x = 342\]
Set greater number as x. x(x-1)=342, according to your problem. When you multiply it out, you have \[x^2-x=342.\] Then, you move 342 to the other side and you have \[x^2-x-342=0.\] Finally, you factor and you are left with (x-19)(x+18) or (x+19)(x-18). This means that x can be \[\pm19\] and \[\pm18\]
which means that the bigger one is 19 or -19, and the smaller is 18, or -18 (positive if 19 is positive, negative if 19 is negative)
Refer to the Mathematica attachment.
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