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Using Substitution 4x-3y=-10 and x=1/4y-1

User McCroskey
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1 Answer

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Answer:

Then the solution is (-1/4, 3)

Explanation:

Start by eliminating the fractional coefficient 1/4: multiply all 3 terms in the second equation by 4. This results in equation (b), below:

4x - 3y = -10 (a)

4x = y -4 (b)

Substitute y - 4 for 4x in equation (a):

y - 4 - 3y = -10

Combining like terms, we get -2y = -10 + 4, or -2y = -6, or y = 3.

Since x = (1/4)y - 1, if y = 3, then x = (1/4)(3) - 1, or x = 3/4 - 1, or x = -1/4

Then the solution is (-1/4, 3)

User Pauleen
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