The origin is at the point (0,0). Therefore, the y-intercept will be 0. For two points to be perpendicular, the slopes must be opposite reciprocals of each other. .5 can be seen as 1/2, so the reciprocal is 2, and it is positive, making that 2 negative. Your equation would be y = -2x.
5/8 is 0.625 , so that would be the decimal for it
A . y = 2(18 + x)
b. y = (8 + x)(10 + x)
or y = x^2 + 80 + 18x
