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Answer two questions about systems [a] and [b]:

System [a]:
4x + 16y = 12
x + 2y = -9
System [b]:
4x + 16y = 12
x + 4y = 3

User TZU
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1 Answer

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Final answer:

To solve system [a], you can use the method of substitution or elimination. The solution to system [a] is x = -15 and y = 3. To solve system [b], you can use the same method. The two equations in system [b] have infinitely many solutions and are dependent. The solution is any point that satisfies the equation, such as (x, y) = (3, 0).

Step-by-step explanation:

System [a]:

4x + 16y = 12

x + 2y = -9

System [b]:

4x + 16y = 12

x + 4y = 3

To solve system [a], we can use the method of substitution or elimination. Let's use elimination:

Multiply the second equation by 2 to match the coefficients of x. This gives:

2x + 4y = -18

Now subtract the second equation from the first equation:

(4x + 16y) - (2x + 4y) = 12 - (-18)

2x + 12y = 30

Simplify the equation:

x + 6y = 15

This new equation can be used with the original second equation to solve for x and y. Substitute the value of (x + 2y) from the second equation into the new equation:

(x + 2y) + 6y = 15

Simplify the equation:

x + 8y = 15

Now we have a system of two equations:

x + 8y = 15

x + 4y = 3

We can subtract the second equation from the first equation to eliminate x:

(x + 8y) - (x + 4y) = 15 - 3

4y = 12

Divide both sides by 4:

y = 3

Now substitute the value of y back into one of the original equations to solve for x:

x + 2(3) = -9

x + 6 = -9

Subtract 6 from both sides:

x = -15

So the solution to system [a] is x = -15 and y = 3.

To solve system [b], we can use the same method. Let's use elimination:

Multiply the second equation by 2 to match the coefficients of x. This gives:

2x + 8y = 6

Now subtract the second equation from the first equation:

(4x + 16y) - (2x + 8y) = 12 - 6

2x + 8y = 6

Simplify the equation:

x + 4y = 3

This new equation can be used with the original second equation to solve for x and y. Substitute the value of (x + 4y) from the second equation into the new equation:

(x + 4y) + 4y = 3

Simplify the equation:

x + 8y = 3

Now we have a system of two equations:

x + 8y = 3

x + 4y = 3

The two equations are the same, so they have infinitely many solutions and are dependent. The solution is any point that satisfies the equation, such as (x, y) = (3, 0).

User Mitchell Walls
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