4 months ago
Q:

The coordinate grid shows the plot of four equations. A coordinate plane is shown with four lines graphed. Line A crosses the x axis at negative 3.2 and has a slope of 4. Line B crosses the x axis at 3 and the y axis at 6. Line C crosses the x axis at 1.5 and the y axis at negative 6. Line D crosses the x axis at negative 3 and the y axis at 3. Which set of equations has (2, 2) as its solution? A and D B and D A and C B and C

Accepted Solution

A:
let m be the slope and b the y-intercept:

m=(y-y)/(x-x) and y=mx+b

Line A 

y=4x-3.2

Line B 

(3,0) and (0,6)

m= 6/-3= -2

y= -2x+b

0=-2(3)+b

b=6

y= -2x+6

Line C

(1.5,0) and (0,-6)

m=-6/-1.5=4

y=4x+b

0=4(1.5)+b

b = -6

y=4x-6

Line D

(-3,0) and (0,3)

m=3/3=1

y=x+b

0=-3+b

b=3

y=x+3