3x=4y
x+y=21
x = 21-y
3(21-y)=4y
63-3y=4y
63=7y
y=9
x+y=21
x+9=21
x=12
answer is (12, 9)
Answer:
Number 4
Step-by-step explanation:
Option B would yield more in the short term but after Option A surpasses it, it would become more profitable.
Answer:
A
Step-by-step explanation:
My brain is big now trust me ;)
Answer:
-0.6 cm/min
Step-by-step explanation:
The formula for the area of a triangle is ...
A = (1/2)bh
Solving for the base, we find ...
b = 2A/h
Then the rate of change of the base is ...
b' = 2(A'h -Ah')/h^2
Filling in the given values, we find the rate of change of the base to be ...
b' = 2((2 cm^2/min)(20 cm) -(160 cm^2)(1 cm/min))/(20 cm)^2
= 2(40-160)/400 cm/min
= -0.6 cm/min
The base is decreasing at 0.6 cm/minute.
Answer: A student who owns a cell phone is more likely to have brought a personal device than not to have brought one.
Step-by-step explanation:
