Answer: <em>"7 is a solution to the original equation. The value –1 is an extraneous solution."</em>
Step-by-step explanation:
The equation
can be solved by squaring both sides:

We can see that -1 and 7 are solutions, but make sure they are not extraneous by substituting them in the original equation:

The square root of 49 equals 7, but the square root of -1 is an imaginary number.
The correct choice is <em>"7 is a solution to the original equation. The value –1 is an extraneous solution."</em>
Answer:
60
Step-by-step explanation:
You need the least common multiple of 5, 3, and 4.
5 = 5, 10, 15, 20, 25... 60
3= 3, 6, 9...60
4=4, 8, 12, ...60
Answer:
Step-by-step explanation:
4/9 to 20/x
cross multiply and divide to get your answer
4 20
9 x
4x=180
x=45
Consider the charge for parking one car for t hours.
If t is more than 1, then the function is y=3+2(t-1), because 3 $ are payed for the first hour, then for t-1 of the left hours, we pay 2 $.
If t is one, then the rule y=3+2(t-1) still calculates the charge of 3 $, because substituting t with one in the formula yields 3.
75% is 75/100 or 0.75.
For whatever number of hours t, the charge for the first car is 3+2(t-1) $, and whatever that expression is, the price for the second car and third car will be
0.75 times 3+2(t-1). Thus, the charge for the 3 cars is given by:
3+2(t-1)+0.75[3+2(t-1)]+0.75[3+2(t-1)]=3+2(t-1)+<span>0.75 × 2[3 + 2(t − 1)].
Thus, the function which total parking charge of parking 3 cars for t hours is:
</span><span>f(t) = (3 + 2(t − 1)) + 0.75 × 2(3 + 2(t − 1))
Answer: C</span>