Answer:
y = 7x + 15
Step-by-step explanation:
total cost = $7 x every hour + $15 renters fee
Answer:
1.) 8.09g ; 2) 206.7 years
Step-by-step explanation:
Given the following :
Half-life(t1/2) of Uranium-232 = 68.9 years
a) If you have a 100 gram sample, how much would be left after 250 years?
Initial quantity (No) = 100g
Time elapsed (t) = 250 years
Find the quantity of substance remaining (N(t))
Recall :
N(t) = No(0.5)^(t/t1/2)
N(250) = 100(0.5)^(250/68.9)
N(250) = 100(0.5)^3.6284470
N(250) = 100 × 0.0808590
= 8.0859045
= 8.09g
2) If you have a 100 gram sample, how long would it take for there to be 12.5 grams remaining?
Using the relation :
N / No = (1/2)^n
Where N = Amount of remaining or left
No = Original quantity
n = number of half-lifes
N = 12.5g ; No = 100g
12.5 / 100 = (1/2)^n
0.125 = (1/2)^n
Converting 0.125 to fraction
(1/8) = 1/2^n
8 = 2^n
2^3 = 2^n
n = 3
Recall ;
Number of half life's (n) = t / t1/2
t = time elapsed ; t1/2 = half life
3 = t / 68.9
t = 3 × 68.9
t = 206.7 years
Answer:
x=5, y=1
Step-by-step explanation:
Isolate x for 5x-3y=22
5x-3y=22
Add 3y to both sides
5x-3y+3y=22+3y
Simplify
5x=22+3y
Divide both sides by 5
5x/5=22/5+3y/5
Simplify
x=22+3y/5
Substitute x=22+3y/5
10*22+3y/5-4y=46
Simplify 10*22+3y/5-4y
10*22+3y/5=2(3y+22)
=2(3y+22)-4y
Expand 2(3y+22)
=6y+44-4y
Simplify 6y+44-4y
=2y+44
Isolate y for 2y+44=46
2y+44=46
Subtract 44 from both sides:
2y+44-44=46-44
Simplify
2y=2
Divide both sides by 2;
2y/2=2/2
Simplify;
y=1
For x=22+3*1/5 substitute y=1
y=22+3*1/5
22+3*1=25
=25/5
Divide the numbers;25/5=5
=5
x=5
The solutions to the system of equations are;
x=5, y=1
Answer: y = -x + 9
Step-by-step explanation:
First, to find the slope of the line we will use: (y₂-y₁)/(x₂-x₁)
Using the two points, we get: (8-1)/(1-8)
Simplify it: 7/-7
Finally, the slope is -1
We can now write: y = -x + b
Next we will plug in a point into the equation we have:
(8,1) --> 1 = -8 + b Then solve algebraically
b = 9
Then finish the equation:
y = -x + 9
