What is the equation of the line passing through (96,72) and (19,4)?

3 Answers
May 7, 2018

The slope is 0.88311688312.

Explanation:

(Y_2 - Y_1)/ (X_2 - X_1) = m, the slope

Label your ordered pairs.

(96, 72) (X_1, Y_1)
(19, 4) (X_2, Y_2)

Plug-in your variables.

(4 - 72)/(19 - 96) = m

-68/-77 = m

Two negatives make a positive, so:

0.88311688312 = m

May 7, 2018

y = = 68/77x - 984/77

Explanation:

Recall;

y = mx + c

m = (y_2 - y_1)/(x_2 - x_1)

y_2 = 4

y_1 = 72

x_2 = 19

x_1 = 96

Inputing the values..

m = (4 - 72)/(19 - 96)

m = (-68)/-77

m= 68/77

The new equation is;

(y - y_1) = m(x - x_1)

Inputing their values..

y - 72 = 68/77(x - 96)

y - 72 = (68x - 6528)/77

Cross multiplying..

77(y - 72) = 68x - 6528

77y - 5544 = 68x - 6528

Collecting like terms..

77y = 68x - 6528 + 5544

77y = 68x - 984

Dividing through by 77

y = = 68/77x - 984/77

May 7, 2018

Point-slope form: y-4=68/77(x-19)

Slope-intercept form: y=68/77x-984/77

Standard form: 68x-77y=984

Explanation:

First determine the slope using the slope formula and the two points.

m=(y_2-y_1)/(x_2-x_1),

where m is the slope, and (x_1,y_1) is one point and (x_2,y_2) is the other point.

I'm going to use (19,4) as (x_1,y_1) and (96,72) as (x_2,y_2).

m=(72-4)/(96-19)

m=68/77

Now use the slope and one of the points to write the equation in point-slope form:

y-y_1=m(x-x_1),

where:

m is the slope and (x_1,y_1) is one of the points.

I'm going to use (19,4) for the point.

y-4=68/77(x-19) larr point-slope form

Solve the point-slope form for y to get the slope-intercept form:

y=mx+b,

where:

m is the slope and b is the y-intercept.

y-4=68/77(x-19)

Add 4 to both sides of the equation.

y=68/77(x-19) +4

Expand.

y=68/77x-1292/77 + 4

Multiply 4 by 77/77 to get an equivalent fraction with 77 as the denominator.

y=68/77x-1292/77+4xx77/77

y=68/77x-1292/77+308/77

y=68/77x-984/77 larr slope-intercept form

You can convert the slope-intercept form to the standard form:

Ax+By=C

y=68/77x-984/77

Multiply both sides by 77.

77y=68x-984

Subtract 68x from both sides.

-68x+77y=-984

Multiply both sides by -1. This will reverse the signs, but the equation represents the same line.

68x-77y=984 larr standard form

graph{68x-77y=984 [-10, 10, -5, 5]}