Answer:
Step-by-step explanation:
[−1,1] and [0,
]
hope this helped :)
H(x)=5x+15+4x+20
if x=4, together it would be 5(4)+15+4(4)+20
h(x)=20+15+16+20=71
Divided by 2, they'd each get 35.5
If Frank worked alone, he'd get 5(4)+15= 35
He'd make more working together.

The unknown b is stuck in the exponent position.
We can can fix that by using logarithms.
Log is the inverse operation of the exponential.
We'll take log of each side.
Log of what base tho?
Well, the base of our exponential is e,
so we'll take log base e of each side.

We'll apply one of our log rules next:

This allows us to take the exponent out of the log,

Another thing to remember about logs:
When the base of the log matches the inside of the log,
then the whole thing is simply 1,



So our equation simplifies to this,

As a final step, divide both sides by 3,

k, hope that helps!
So we solve for each
70% of 100=70
students who didn't buy lunch=100-70=30
some of the 70 left so that the students who bought lunch, are 60% of those who are left
we know that the students who didn't buy lunch didn't change number so therefor
100% of students left-60%=40%= students that didn't buy lunch=30 so
40%=30
20%=15
100%=75
there were 75 students lfet in the cafeteria