Solve using substitution technique; -3x+y=2, 12x-4y=-8

Mathematics

1 answer:

vladimir1956 [14]4 years ago

4 0

The first equation is easier to solve for y than is the 2nd: y = 3x+2. Subst. 3x+2 for y in the second equation:

12x - 4(3x+2) = -8

Expanding, 12x =12x -8 = -8

This is always true, no matter the value of x. Thus, the solution set is "all real numbers."

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Marta_Voda [28]

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3 years ago

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AVprozaik [17]

Answer:

The correct option is;

False

Step-by-step explanation:

The coefficient of x^k·y^(n-k) is nk, False

The kth coefficient of the binomial expansion, (x + y)ⁿ is $\dbinom{n}{k} = \dfrac{n!}{k!\cdot (n-k)!} = C(n,k)$