Question

4 multiple choice 4 points
what is the value of x in the solution of the system of equations 3x + 2y = 12 and 5x - 2y = 4?
3
8
4
2
5 multiple choice 4 points
which ordered pair is the solution set for this system of equations?
x + y = 8
y = x - 3
(4,4)
(2.5,5.5)
(5.5,2.5)
(4,1)

Explanation:

Step1: Add the two equations

$$(3x + 2y) + (5x - 2y) = 12 + 4$$
$$8x = 16$$

Step2: Solve for x

$$x = \frac{16}{8} = 2$$

Step3: Substitute y into first equation

$$x + (x - 3) = 8$$
$$2x - 3 = 8$$

Step4: Solve for x

$$2x = 11$$
$$x = 5.5$$

Step5: Find y using x value

$$y = 5.5 - 3 = 2.5$$

Answer:

1. 2
2. (5.5, 2.5)