<span>The phone company charges 10 cents to connect a call for one minute and 8 cents per minute after that.
We call x minute to talk after the first minute.
We have 10+8x</span>≤100 (cents)
and 8x≤100-10
or 8x≤90 and x≤90:8
and x≤11.25
So: <span>How long could you talk on the phone for 1 dollar: it is 11 minute and 15 seconds</span>
He will have 5.75 change left
See each answer below.
1) If we subtract 7 from both sides and try to take the square root, we are taking the square root of -7. Therefore, there are no solutions.
2) Dividing by 3 and taking the square root gives an answer of 0.
3) Add 4, multiply by 4 and finally take the square root of each side.You will get positive or negative four.
4) Divide by 4 and then take the square root. You have positive or negative 5/2.
