Answer:
b=8
Explanation:
Perpendicular lines are negative and reciprocal; when you multiply the slopes together, the result is -1.
we are given the line y=-3x-5
we need to find the slope of the new line. To do that, we can use this equation:
-3m=-1
divide by -3 on both sides
m=1/3
so the slope of the perpendicular line is 1/3
We can write our line in slope-intercept form, which is y=mx+b, where m is the slope and b is the y intercept, which is what we need
so far our equation is:
y=1/3x+b
we need to find b
we can substitute the point (-3,7) into the equation, since the line will pass through it to solve for b
so:
7=1/3(-3)+b
7=-1+b
8=b
so the y intercept of the line is 8; as a point it's (0,8)
hope this helps!