Question

6. What type of slope does the equation

7x + 3y = 15 have? (Hint: convert to slope
intercept form.)
A) positive
B) Negative
C) Zero
D) Undefined

Answer 1

Answer: B) Negative

Explanation:

We can convert the line 7x + 3y = 15 into the slope-intercept form (y = mx + c) by making y the subject of the equation. In this form the coefficient of x (m) is the slope.

Since 7x + 3y = 15

3y = -7x + 15

y = - ⁷/₃x + 5

∴ the slope is NEGATIVE.

Check your answer:

A line with a negative slope is highest to the left and lowest to the right. This is because when x values increase, the y values decrease, and when x values decrease, y values increase (the two variables are negatively related). If we graph the line this should be true, and it is.