what is the equation in standard form of a perpendicular line that passes through 5,1?

y+4=-4(x-2)

Question

what is the equation in standard form of a perpendicular line that passes through 5,1?

y+4=-4(x-2)

lucaz · Answer

you need a slope, the perpendicular line has the negative reciprocal slope

anonymous · Answer

i keep getting the answer wrong

lucaz · Answer

what is the slope of the line that passes through the point (5,1) ?

lucaz · Answer

you need this information

anonymous · Answer

2/-4

anonymous · Answer

right?

lucaz · Answer

$$\large{
-\frac{2}{4}
}$$
this is the slope?

anonymous · Answer

yes im pretty sure

lucaz · Answer

it simplifies to -1/2, so now you get the reciprocal neg. slope
-1/(-1/2) = 2 and use the standard form
$$\large{
y-y_1=m(x-x_1)}$$

lucaz · Answer

this y+4=-4(x-2) is the given line?

anonymous · Answer

yes that is what i did and got y-1=2/-4(x-5)

lucaz · Answer

if this is the given line the slope is -4, and it's neg. reciprocal is 1/4

anonymous · Answer

but i dont get what y equals? because in another question i have to graph the points?

anonymous · Answer

and i got x=1 but i dont know what y is?

lucaz · Answer

this is just a function, if you have x=1 you replace x by 1 and calculate y

anonymous · Answer

but what about 5,1?

lucaz · Answer

like f(x) or y = 3x+1, if x=1 -> 3(1)+1 = 4

lucaz · Answer

yeah, the slope is -4, so the reciprocal is 1/4
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