Answer: 620
Step-by-step explanation:
$40 x 5.5 hrs = $220 This means that she earned $220 tutoring the first student.
$40 x 10 hrs = $400 She earned $400 tutoring the second student.
$220 + $400 = $620 She earned $620 in total that week.
<span>Let x be Joanna's heart rate immediately after running one mile.
After this heart rate x decreased by 2 over 5, Joanna's heart rate was 60 beats per minute. We can set up an equation to solve this question.
x - (2/5) x = 60
(3/5) x = 60
x = (5/3) 60
x = 300 / 3
x = 100
Joanna's heart rate immediately after running one mile was 100 beats per minute.</span>
The answer would be C, 15
Let the two numbers be x and y.
We have x+y=45
⇒ y= 45-x.
The two numbers multiply and get 121, so we have another equation:
x*y = 121 (1)
Plug y= 45-x in (1), we have:
x* (45-x)=121
⇒ 45x - x^2 = 121 (distributive property)
⇒ x^2 - 45x = -121 (multiply -1 on both sides)
⇒ x^2- 45x + 121= 0
⇒ x= 42.128 or x= 2.872
y= 45- 42.128= 2.872
or y= 45- 2.872= 42.128.
Because it does not matter what number, x or y, is larger, the two numbers are 2.872 and 42.128.
Hope this helps~