Answer:
x = 6, y = -6
Step-by-step explanation:
solve for x and y
x + 3y = -12
y + 3 = -x + 3
add
(x + 3y) + -x + 3 = -12 + y + 3
3y + 3 = y - 9
2y + 3 = -9
2y = -12
y = - 6
x + 3(-6) = -12
x - 18 = -12
x = 6
Answer:
x= -4
Step-by-step explanation:
Simplifying
5x + -4 = 7x + 4
Solving
-4 + 5x = 4 + 7x
Move all terms containing x to the left, all other terms to the right.
Add '-7x' to each side of the equation.
-4 + 5x + -7x = 4 + 7x + -7x
Combine like terms: 5x + -7x = -2x
-4 + -2x = 4 + 7x + -7x
Combine like terms: 7x + -7x = 0
-4 + -2x = 4 + 0
-4 + -2x = 4
Add '4' to each side of the equation.
-4 + 4 + -2x = 4 + 4
Combine like terms: -4 + 4 = 0
0 + -2x = 4 + 4
-2x = 4 + 4
Combine like terms: 4 + 4 = 8
-2x = 8
Divide each side by '-2'.
x = -4
Simplifying
x = -4
Answer:
225.78 grams
Step-by-step explanation:
To solve this question, we would be using the formula
P(t) = Po × 2^t/n
Where P(t) = Remaining amount after r hours
Po = Initial amount
t = Time
In the question,
Where P(t) = Remaining amount after r hours = unknown
Po = Initial amount = 537
t = Time = 10 days
P(t) = 537 × 2^(10/)
P(t) = 225.78 grams
Therefore, the amount of iodine-131 left after 10 days = 225.78 grams
