Question

Examine the system of equations. y = 3 2 x − 6, y = −9 2 x + 21 Use substitution to solve the system of equations. What is the value of y? y =

Answer 1

Answer:

3/4

Step-by-step explanation:

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Answer 2

Answer:

y = -4/9

Step-by-step explanation:

Given the system of equations y = 3/2 x − 6, y = −9/2 x + 21, since both expressions are functions of y, we will equate both of them to find the variable x;

3/2 x − 6 = −9/2 x + 21,

Cross multiplying;

3(2x+21) = -9(2x-6)

6x+63 = -18x+54

collecting the like terms;

6x+18x = 54-63

24x = -9

x = -9/24

x = -3/8

To get the value of y, we will substitute x = -3/8 into any of the given equation. Using the first equation;

y = 3/2x-6

y = 3/{2(-3/8)-6}

y = 3/{(-3/4-6)}

y = 3/{(-3-24)/4}

y = 3/(-27/4)

y = 3 * -4/27

y = -4/9

Hence, the value of y is -4/9