Question

(15 POINTS!)

The slope of the line passing through the points (7, 5) and (21, 15) is

5/7
7/5
5
7

Another line with a slope that is one-third that of the slope you just calculated passes through the origin and the point

3, 5
3, 7
21, 5
21, 7

Answer 1

1) 5/7

2) (21, 5)

Explanation:

1) The slope of the line passing through the points (7, 5) and (21, 15) is

`(15-5)/(21-7) =(10)/(14)=(5)/(7)`

because slope is (difference of y)/(difference of x)

the first option is correct

2) 1/3 of 5/7 is 5/21.

The line will be in the form of

y = 5/21 x + b where b is the y-intercept.

Find the complete equation by plugging in (0,0) since it passes thorugh the origin.

0 = 5/21 (0) +b

0=0+b

b=0

The equation: y=5/21 x

let's check each option by plugging in.

y= 5/21 (3)= 5/7

y is not 5 but 5/7

y= 5/21 (3)= 5/7

y is not 7 but 5/7

y= 5/21 (21) = 5

y is 5, which matches with the answer choice!!!

y= 5/21 (21) = 5

y is 5, not 7.

The third option is correct