In each case, you solve for y. You do this by subtracting the x term and dividing by the coefficient of y. The resulting x coefficient is the slope.
-2x + 5y = 15
5y = 2x + 15 (add 2x. Equivalently, subtract -2x.)
y = (2/5)x + 3 (divide by 5)
The slope is 2/5.
3x + 7y = 0
7y = -3x (subtract 3x)
y = (-3/7)x (divide by 7)
The slope is -3/7.
______
If you were paying attention, you noticed that the slope of an equation in the form of
ax + by = c
is given by
slope = -a/b
With this knowledge, you can write down the slope by looking at the equations.
-2x + 5y = 15
5y = 2x + 15 (add 2x. Equivalently, subtract -2x.)
y = (2/5)x + 3 (divide by 5)
The slope is 2/5.
3x + 7y = 0
7y = -3x (subtract 3x)
y = (-3/7)x (divide by 7)
The slope is -3/7.
______
If you were paying attention, you noticed that the slope of an equation in the form of
ax + by = c
is given by
slope = -a/b
With this knowledge, you can write down the slope by looking at the equations.
