write an equation of the line through the given point with the given slope. help!!?

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selenacf

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Also, write the equation in slope intercept form.

46) (2,2); m= - 3/4

A) y= -3/4x + 7/2
B) y= - 3/4x + 2/7
C) y= -4/3x + 7/2
D) y= -3/4x - 7/2

the answer is A. but i need help in the step process very carefully. I started to use the given info. and put it into the formula y= mx + b. so it would be 2 = -3/4(2) + b. then i got a lil stuck. so i started to multiply -3/4 by 2....which gives me -3/2 when simplified. I don't know if this is right...or the right way to do it. Somebody help please. is there another way to do this??? because i just don't get it.
 
Hi there,

You were doing it right. After plugging all the numbers in, you will get:

2 = -3/4(2) + b

Then, multiply out the fraction to get:

2 = -3/2 + b

Finally, add 3/2 to both sides. You will get:

2 + 3/2 = b

Write 2 as the fraction 4/2 (simply multiply by 2/2) and you will get:

7/2 = b

Plug b back into the formula y=mx+b and you will get "A".
 
Here slope m = -3/4
Thus
y = -3x/4 + c .............. [1]
To find c [1] is pases point (2, 2)
So==> 2 = -3*2/4 + c
OR c = 2 + 1.5 = 3.5
Hence the line is :
y = -3x/4 + 3.5
A N S W E R
 
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