Answer:
Associative properties of multiplication
Step-by-step explanation:
The point-slope form of an equation of a line:

m - slope
We ahve the slope m = 1/2 and the point (-2, 1). Substitute:

- point-slope form
Covert to the slope-intercept form (y = mx + b):
<em>use the distributive property</em>
<em>add 1 to both sides</em>
- slope-intercept form
Convert to the standard form (Ax + By = C):
<em>multiply both sides by 2</em>
<em>subtract x from both sides</em>
<em>change the signs</em>
- standard form
Convert to the general form (Ax+By+C=0):
<em>add 4 to both sides</em>
- general form
2x - y = -24
x + 7y = 3
Solve one equation for a variable and plug the resulting value into the second equation.
x + 7y = 3 Subtract 7y from both sides
x = -7y + 3
Now, plug that x-value into the x of the first equation.
2x - y = -24 Plug in the x-value
2(-7y + 3) - y = 24 Use the Distributive Property
-14y + 6 - y = -24 Combine like terms (-14y and -y)
-15y + 6 = -24 Subtract 6 from both sides
-15y = -30 Divide both sides by 15
y = 2
Next, plug the y-value back into the second equation.
x + 7y = 3 Plug in the y-value
x + 7(2) = 3 Multiply
x + 14 = 3 Subtract 14 from both sides
x = -11
y = 2 and x = -11