If the slopes of the 2 lines are equal then they are parallel.
If m1m2 = -1 (where m1 and m2 are the slopes of the 2 lines) then they are perpendicular.
If the 2 slopes do not match either the first or second conditions then they are neither parallel or perpendicular.
Answer:
a) y = 1/2x + 5/2
y = 2/5x + 29/5
b) hair will be 19 inches for both at 33 months
Step-by-step explanation:
a) rate of growth of friend's hair: (3, 4) (8, 6.5)
(6.5 - 4) ÷ (8 - 3) = 2.5/5 or 1/2
find the y-intercept of equation for growth of friend's hair:
y = mx + b
4 = 1/2(3) + b
4 = 3/2 + b
8/2 - 3/2 = b
5/2 = b
equation for growth of friend's hair:
y = 1/2x + 5/2
rate of growth of cousin's hair: (3, 7) (8, 9)
(9 - 7) ÷ (8 - 3) = 2/5
find the y-intercept of equation for growth of cousin's hair:
y = mx + b
9 = 2/5(8) + b
9 = 16/5 + b
45/5 - 16/5 = b
29/5 = b
equation for growth of cousin's hair:
y = 2/5x + 29/5
b) y = 1/2x + 5/2
y = 2/5x + 29/5
1/2x + 5/2 = 2/5x + 29/5
5/10x + 25/10 = 4/10x + 58/10
1/10x = 33/10
10x = 3300
x = 33
Equation of a line: y = mx + b
m = slope(rise/run), b = y-intercept
1/2
y = 1/2x - 3
-7/4
y = -7/4x +4
-1/2
y = -1/2x - 3
-1/4
y = -1/4x + 2
1
y = x
-1
y = -x
Answer:
Step by step explanation:
