Which of the following is the correct expansion of (x + 3)(x - 4)?

Mathematics

1 answer:

arlik [135]3 years ago

3 0

Using FOIL (First, Outer, Inner, Last):

(x+3)(x-4)

FIRST: multiply x times x to get x^2.

OUTER: multiply x times -4 to get -4x.

INNER: multiply 3 times x to get 3x.

LAST: multiply 3 times -4 to get -12.

Your expression now looks like:

x^2-4x+3x-12

Combine like terms.

x^2-x-12

The answer is D. x^2-x-12.

I hope this helps :)

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Read 2 more answers

Enter as a integer or decimal

valentina_108 [34]

Answer:

x = - 6

Step-by-step explanation:

Given

4(x + 6) - 2x = 12 ← distribute and simplify left side

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