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Y=4x+3 y=7+3x solve this system of equations using the substitution method

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Answer:

y = 19; x = 4

Explanation:

Step 1: Isolate x in y = 4x + 3:

Before we can start solving the system, we'll first need to isolate x in the first equation using the following steps:

Subtract 3 from both sides:

(y = 4x + 3) - 3

y - 3 = 4x

Divide both sides by 4 to isolate x:

(y - 3 = 4x) / 4

1/4y - 3/4 = x

Step 2: Substitute 1/4y - 3/4 = x for x in y = 7 + 3x to solve for y:

Now we can substitute 1/4y - 3/4 = x for x in y = 7 + 3x to first solve for y:

y = 7 + 3(1/4y - 3/4)

y = 7 + 3/4y - 9/4

(y = 3/4y + 19/4) - 3/4y

(1/4y = 19/4) / 1/4

y = 19/4 * 4

y = 19

Thus, y = 19

Step 3: Plug in 19 for y in y = 4x + 3 to solve for x:

Now we can solve for x by plugging in 19 for y in y = 4x + 3:

(19 = 4x + 3) - 3

(16 = 4x) / 4

4 = x

Thus, x = 4

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