Expand and simplify (x+6)(x+4)
Answer: x2+10x+24
Method: A handy way of knowing how to expand brackets involves the pneumonic FOIL:
- F stands for First, so we multiply the first term in the first bracket by the first term in the second bracket: x * x = x2
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O stands for Outers, so we multiply the outer terms in both brackets. These are the terms which are furthest away from each other. We can see that the terms which are furthest away from each other in this question are x and 4: x * 4 = 4x
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I stands for Inners, so we multiply the inner terms in both brackets. These are the terms which are closest to each other. We can see that the terms which are closest to each other are 6 and x: 6 * x = 6x
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L stands for Last, so we multiply the last term in the first bracket by the last term in the second bracket: 6 * 4 = 24.
Finally, now that we have multiplied each of the terms together using FOIL, we can see that (x+6)(x+4) expands to give x2 + 4x + 6x + 24 = x2 + 10x + 24
