Answer:
Use google scooby it's easier than this way.
Step-by-step explanation:
Answer:
The x-coordinate of the point changing at ¼cm/s
Step-by-step explanation:
Given
y = √(3 + x³)
Point (1,2)
Increment Rate = dy/dt = 3cm/s
To calculate how fast is the x-coordinate of the point changing at that instant?
First, we calculate dy/dx
if y = √(3 + x³)
dy/dx = 3x²/(2√(3 + x³))
At (x,y) = (1,2)
dy/dx = 3(1)²/(2√(3 + 1³))
dy/dx = 3/2√4
dy/dx = 3/(2*2)
dy/dx = ¾
Then we calculate dx/dt
dx/dt = dy/dt ÷ dy/dx
Where dy/dx = ¾ and dy/dt = 3
dx/dt = ¾ ÷ 3
dx/dt = ¾ * ⅓
dx/dt = ¼cm/s
The x-coordinate of the point changing at ¼cm/s
Answer:
Step-by-step explanation:
- x + y + z = -3 --> (1)
- 3y - z = 4 --> (2)
- 2x - y - 2z = -5 --> (3)
<u>Add up (1) and (2)</u>
- x + 3y + y + z - z = -3 + 4 ⇒ x + 4y = 1 --> (4)
<u>Double (2) and subtract from (3)</u>
- 2x - y - 2z - 2(3y - z) = -5 - 2(4) ⇒ 2x - y - 2z - 6y + 2z = -5 - 8
- 2x - 7y = -13 --> (5)
<u>Double (4) and subtract (5)</u>
- 2(x + 4y) - 2x + 7y = 2 + 13 ⇒ 2x + 8y - 2x + 7y = 15 ⇒ 15y = 15 ⇒ y = 1
<u>Finding x</u>
- x + 4(1) = 1 ⇒ x = 1 - 4 ⇒ x = -3
<u>Finding z</u>
<u>So the answer is: </u>
Andrew will run 32 miles.
Explanation:
If you divide the time Andrew ran by the miles he ran, you’ll get 7.5 minutes per mile. Then, if you divide 240 minutes by 7.5, you get 32 miles.