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Which of the ordered pairs of numbers (c, d) satisfies the simultaneou
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31 Jan 2022, 04:45
31 Jan 2022, 04:45
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Which of the ordered pairs of numbers \((c, d)\) satisfies the simultaneous equations shown?
\(c+2d=6\)
\(-3c-6d=-18\)
A (-2, 4)
B (-1, -3)
C (0, 2)
D (2, 1)
E (3, -9)
\(c+2d=6\)
\(-3c-6d=-18\)
A (-2, 4)
B (-1, -3)
C (0, 2)
D (2, 1)
E (3, -9)
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Which of the ordered pairs of numbers (c, d) satisfies the simultaneou
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04 Feb 2022, 06:53
04 Feb 2022, 06:53
1
Carcass wrote:
Which of the ordered pairs of numbers \((c, d)\) satisfies the simultaneous equations shown?
\(c+2d=6\)
\(-3c-6d=-18\)
A (-2, 4)
B (-1, -3)
C (0, 2)
D (2, 1)
E (3, -9)
\(c+2d=6\)
\(-3c-6d=-18\)
A (-2, 4)
B (-1, -3)
C (0, 2)
D (2, 1)
E (3, -9)
Before we try to solve the given system of equations, we might first consider whether the system can be solved at all.
Remember that, if the two equations are identical, then there will be infinitely many solutions to the system.
Notice that, if we take the top equation, \(c+2d=6\), and multiply both sides by -3, we get: \(-3c-6d=-18\), which is the same as the bottom equation.
Since our two equations are identical, there are infinitely many solutions to the system.
This means, we'll have to test each answer choice to see whether it lies on either of the equations.
A (-2, 4)
Let's see if c = -2 and d = 4 is a solution to the top (easier-to-use) equation by plugging them into the equation.
We get: \((-2)+2(4)=6\). It WORKS!!
Answer: A
gmatclubot
Which of the ordered pairs of numbers (c, d) satisfies the simultaneou [#permalink]
04 Feb 2022, 06:53
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