Answer: plants are same height in 30 days; Plant A is tallest in 6 weeks
Step-by-step explanation:
x = number of days
4 + (2/3)x = 9 + (1/2)x
(2/3)x - (1/2)x = 9 - 4
(1/6)x = 5
x = 30, number of days for Plant A and Plant B to be same height.
6 wks = 42 days
Plant A in 42 days: 4 + (2/3)(42) = 32 inches
Plant B in 42 days: 9 + (1/2)(42) = 30 inches
#1)
Answer:
x=1 and y=12
Explanation:
y=5x+7
y=2x+10
This system should use substitution because the value of y is given in terms if x.
Substitution:
5x+7=2x+10
Solve:
3x=3
x=1
Substitute x to solve for y by plugging x into one if the original equations(doesn’t matter which one is used).
y=5x+7
y=5(1)+7
y=5+7
y=12
#2)
Answer:
x=-8 and y=2
Explanation:
y=2x+18
9y=-2x+2
This system also uses substitution. The value of y us already given in terms if c in the first equations, so we will substitute in the second equation.
Substitute:
9(2x+18)=-2x+2
Solve:
18x+162=-2x+2
20x=-160
x=-8
Now that we have the value if x, plug it into one of the original equations(doesn’t matter which equation) and substitute to find y.
y=2x+18
Substitute:
y=2(-8)+18
Solve:
y=-16+18
y=2
Answer:
8
Step-by-step explanation:
3(2)-2(1-2) / 3-2
6-2(-1) / 1
6 + 2 / 1
8 / 1
= 8
