Answer:
Step-by-step explanation:
7x - 9 = x + 3
6x - 9 = 3
6x = 12
x = 2
7(2) - 9 + 2 + 3
14 - 9 + 5
5 + 5 = 10
Answer:
2.5 miles
Step-by-step explanation:
The relation between time, speed, and distance is ...
distance = speed × time
We can define t to be Stanley's swimming time. Then t+0.5 was his running time, and 2(t+0.5) was his biking time. His total distance covered is ...
64 = 9(t +0.5) +16(2(t +0.5)) +2.5(t)
64 = 43.5t +20.5 . . . . . . . simplify
43.5 = 43.5t . . . . . . . . . subtract 20.5
t = 1 . . . . . . . . . . . . . . divide by the coefficient of t
Stanley swam for 1 hour, so the distance he covered while swimming was ...
(2.5 mi/h)(1 h) = 2.5 mi
Stanley covered 2.5 miles while swimming.
_____
<em>Additional comment</em>
Stanley ran for 1.5 hours, covering 9×1.5 = 13.5 miles. He biked for 3 hours, covering 16×3 = 48 miles. His total distance was 2.5 +13.5 +48 = 64 miles, as given.
• First way to solve:
We'll manipulate the expression of the equation:

If we have y=0:

Then, the function has one real zero (x=3) and two imaginary zeros (4i and -4i).
Answer: B
• Second way to solve:
The degree of the function is 3. So, the function has 3 complex zeros.
Since the coefficients of the function are reals, the imaginary roots are in a even number (a imaginary number and its conjugated)
The function "has only one non-repeated x-intercept", then there is only one real zero.
The number of zeros is 3 and there is 1 real zero. So, there are 2 imaginary zeros.
Answer: B.
You would get $3 because the conversion rate is 1:3 so divide 9 by three