Question

write the equation of the line which passes through (2,-3) and is perpendicular to y=4x+7 in standard form

Answer 1

Perpdinduclar lines' gradient multiply to give -1

y = 4x+7

The gradient of the perpindcular line will be "-1/4"
m = -1/4

y=mx+b

you know the line runs through points (2,-3). You can substitute these values into your formula along with m to solve for b (y intercept)

-3 = -1/4x3 +b
-3 = -0.75+b
b = -2.25

y=mx+b
y = -1/4-2.25

Hope this helped. Let me know if you didn't understand how I got this answer :)

Answer 2

Where I multiplied with a 3 it should be a 2, my bad. This will give a answer of -2.5 ):

Let me rewrite this.

-3 = -1/4x2 +b
-3 = -0.5+b
b = -2.5

Answer 3

is this like y =mx+b