4b²+20b+25=0
Divide everything by 4
b²+5b+ 6.25=0
use the quadratic formula
x= (-b+ or - √b²-4ac) /2a
x= (-5 + or - √5²-4*1*6.25) /2(1)
x= -5/2 so
in this case, b= -5/2
Answer:
that not 20 point that 10
Step-by-step explanation:
1. Multiply each equation so they end up with the same coefficient
2. Subtract your second equation from the first
3. Solve for one of the variables (I tend to solve an equation that only contains 2 variables if possible. So it would be if you have one question with x and y, solve for the easier one)
4. Substitute the variable you found in the least step into one of the other equations and find a second variable.
5. Substitute both variables you found into the last equation and there you should be left with x, y, and z :))
I hope this helped sksjsk if it didn’t I could write it out to hopefully help more :)
Answer:
7 years (This answer is to the nearest year)
Step-by-step explanation:
The way you could work this out is by trial and error. 11 % a year means that its population increases by 4400 annually. 40,000 X 1.11^1 gives you the amount it would be after one year (44000). I got the 1.11 because of the percentage (0.11) plus the amount you need to do percentage increase (1). Then all you do is keep on going up till you hit the number you need (80,000) after about 7 years the total would have hit 80,000 and would have actually went past it (83046)