Answer:
5
Step-by-step explanation:
Remember that the slope of a line that is perpendicular to a given line is the negative reciprocal of the slope of the given line.
Here we are given the line y = -(1/5)x - 9. The slope is (-1/5). The negative reciprocal of this is +5. That's the answer you wanted.
Here you go
X=21
5x(-3x) -2= 3x(-3x) +40
2x-2(+2)=40(+2)
2x=42
