SOLUTION: (7p-6)(6p+5) why is 42p2-30 wrong

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Question 592008: (7p-6)(6p+5)
why is 42p2-30 wrong
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
You need to apply this general rule:
+%28+a+%2B+b+%29%2A%28+c+%2B+d+%29+=+a%2Ac+%2B+a%2Ad+%2B+b%2Ac+%2B+b%2Ad++
applying this:
+%287p+-+6%29+%2A+%286p+%2B+5%29+=+42p%5E2+%2B+35p+-+36p+-+30+
+42p%5E2+-+p+-+30+