y=mx+b m=slope b=y intercept perpendicular lines have slopes that multiply to get -1
so
given y=0.5x-9 the slope is 0.5 0.5 times what=-1? times both sides by 2 what=-2
so the slope of the perpendicular line is -2 y=-2x+b find b given (7,10) x=7 and y=10 is one solution plug it in 10=-2(7)+b 10=-14+b add 14 both sides 24=b the equation is y=-2x+24