Question

Find an equation of the line containing (-3,4) and having slope -2. If this line contains the points (a,8) and (5,b), find a and b.

PLEASE HELPPPPPP ANYBODY??? IT IS DUE TODAY!!!

Answer 1

Explanation:

Remark

The slope intercept line is written as y = mx + b in it's general form.

You can get the slope, m, immediately because it is given as -2

So far what you have is y = -2x + b

y intercept

To get the y intercept, use the point (-3 , 4)

x = - 3

y = 4

4 = -2*(-3) + b

4 = 6 + b Subtract 6 from both sides

4 - 6 = 6-6 + b

b = - 2

Line

y = -2x - 2

(a,8)

y = -2a - 2

8 = -2a - 2 Add 2 to both sides

8 +2 = -2a -2+2 Combine

10 = - 2a Divide by - 2

10/-2 = a

a = -5

(5,b)

y = -2x - 2

x = 5

y = b

b = -2*5 - 2

b = -10 - 2

b = - 12