A caterpillar crawling in a straight line across a coordinate plane starts at point (-3, -4) and ends at point (25, 38). Counting the start point and end point, how many
points with integer coordinates does the caterpillar touch?

9514 1404 393

  15

Step-by-step explanation:

In vector form, the equation of point p on the line can be written as ...

  p = (-3, -4) +t(25 -(-3), 38 -(-4)) . . . . . for some scalar t

  p = (-3, -4) +t(28, 42)

  p = (-3, -4) +14t(2, 3)

where t takes on any value between 0 and 1.

If we let t = n/14 for some integer 0 ≤ n ≤ 14, then the coordinates of point p will be integers.

There are 15 values that n can have in the allowed range.

The caterpillar touches 15 points with integer coordinates.

step-by-step explanation:

i think something is missing in your question because y-1=(x-12) would not pass through the point (-4,-3). because if you replace x by -4 your are supposed to find y=-3 which is not the case her. if you replace x by -4 you find =-15.

i assume the right equation is y-1=1/4*(x-12) because this one is passing through both your points (if you are interested to know how i found that out i can tell you).

in this equation if i replace x by -4 i find y=-3 and if i replace x by 12, i find y=1 so the line representing this equation is passing through those 2 points.

then the standard form of the equation is finding an expression of y in function of x

y-1=1/4*(x-12)

y=x/4-3+1

y=x/4-2

hope that .

do you confirm there was a mistake in the question?