Answer:
13.86 ft/sec
Step-by-step explanation:
If we let x = distance batter has run at time t and D = distance from second base to the batter at time t, then we know 
and we want 
when he is halfway (at x = 45).
Using Pythagoras theorem
When x=45
Thus, when the batter is halfway to first base, the distance between second base and the batter is decreasing at the rate of about 13.86 ft/sec.
A) I would make the positive integer x and then form an equation.
x + 30 = x^2 - 12
x + 42 = x^2
0 = x^2 - x - 42 this can be factorised
(x - 7) ( x + 6) Therefore x = 7 or x = -6
Since the question asks for a positive integer the answer is 7.
B) two positive numbers x and y.
X - y = 3
x^2 + y^2 = 117
Use these simultaneous equations to figure out each number.
Rearrange the first equation
x = y + 3
Then substitute it into the second equation.
(y+3)^2 + y^2 = 117
y^2 + 6y + 9 + y^2 = 117
2y^2 + 6y - 108 = 0
then factorise this.
(2y - 12) (y + 9)
This means that y = 6 or y = -9 but it’s 6 because that’s the only positive number.
Use y to find x
x = y + 3
x = 6 + 3
x = 9
So the answers are x = 9 and y = 6.
Answer:
3 5/9
Step-by-step explanation
you flip 9/8 to 8/9 and multiply... you get 32/9=3 5/9
Step-by-step explanation:
80:100=x:20
x=80×20/100=16
