Question

write the standard form of the line that passes through the given point. include your work in your final answer. (-8,0) and (1,5)

Answer 1

9y - 5x = 40

Explanation:

The point (-8, 0) is the x-intercept of this line. The jump as x increases from -8 to 1, is 9; this is the 'run.' The jump as y increases from 0 to 5 is 5; this is the 'rise.' Thus, the slope of this line is

m = rise/run = 5/9

Start with the slope-intercept form of the equation of a line: y = mx + b. If y = 0, x = -8 and m = 5/9, then:

0 = (5/9)(-8) + b. Solve for the y-intercept, b:

0 = -40/9 + b, so b = 40/9, and the equation in slope-intercept form is

y = (5/9)x + 40/9

To obtain the standard form equation, multiply all three terms by 9 to clear out the fractions: 9y = 5x + 40, or

9y - 5x = 40