The third choice, 4x²+18x+0.25=0, is correct.
The frame will have the same thickness on both sides of the mirror. Therefore we add 5+x+x to get the total length, and we have 4+x+x to get the total width.
The area is found by multiplying the total width and total length:
A=(5+x+x)(4+x+x)
A=(5+2x)(4+2x)
Multiplying the binomials, we have:
A=5*4+5*2x+2x*4+2x*2x
A=20+10x+8x+4x²
A=20+18x+4x²
We know that the area is 19.75:
19.75=20+18x+4x²
We need quadratics set equal to 0, so subtract 19.75 from each side:
19.75-19.75 = 20+18x+4x²-19.75
0=0.25+18x+4x²
In standard form, it will be:
4x²+18x+0.25=0
Answer: the population be after 10 years is 289145
Step-by-step explanation:
The growth rate is exponential. We would apply the formula for exponential growth which is expressed as
y = b(1 + r)^t
Where
y represents the population after t years.
t represents the number of years.
b represents the initial population.
r represents rate of growth.
From the information given,
b = 210000
r = 3.25% = 3.25/100 = 0.0325
t = 10 years
Therefore,
y = 210000(1 + 0.0325)^10
y = 210000(1.0325)^10
y = 289145
-4x is the slope and -12 is the y-intercept
Answer:
option-B
Step-by-step explanation:
we are given system of inequality as
now, we can check solution
At (0,0):
we can plug x=0 and y=0
and check inequality
so, this is FALSE
now, we can check second inequality
So, this is TRUE
so, option-B
