MathDB
Two Linear Equations

Source:

March 25, 2006
analytic geometry

Problem Statement

Let mm be a positive integer and let the lines 13x+11y=70013x+11y=700 and y=mx1y=mx-1 intersect in a point whose coordinates are integers. Then mm is: (A) 4(B) 5(C) 6(D) 7(E) one of the integers 4,5,6,7 and one other positive integer\text{(A)} \ 4 \qquad \text{(B)} \ 5 \qquad \text{(C)} \ 6 \qquad \text{(D)} \ 7 \qquad \text{(E)} \ \text{one of the integers}~ 4,5,6,7~\text{and one other positive integer}