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
Question
Answer:
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
solved
general
11 months ago
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