Hello Determine the number of solutions for the given system. y=−4x+7 12x+3y=21 is it one solution , infinitely many solutions or no solution

Answer 1

solve each equation for y

if the result is the same x coefficient and same constant term, then there are an infinite number of solutions.

Graphically they are the same line. the "two" lines "intersect" in an infinite number of points.