Answer:
x = 5/39
, y = 539/39
Step-by-step explanation:
Solve the following system:
{y - 2.5 x = 13.5
12.25 x - y = -12.25
In the first equation, look to solve for y:
{y - 2.5 x = 13.5
12.25 x - y = -12.25
y - 2.5 x = y - (5 x)/2 and 13.5 = 27/2:
y - (5 x)/2 = 27/2
Add (5 x)/2 to both sides:
{y = 1/2 (5 x + 27)
12.25 x - y = -12.25
Substitute y = 1/2 (5 x + 27) into the second equation:
{y = 1/2 (5 x + 27)
1/2 (-5 x - 27) + 12.25 x = -12.25
(-5 x - 27)/2 + 12.25 x = 12.25 x + (-(5 x)/2 - 27/2) = 9.75 x - 27/2:
{y = 1/2 (5 x + 27)
9.75 x - 27/2 = -12.25
In the second equation, look to solve for x:
{y = 1/2 (5 x + 27)
9.75 x - 27/2 = -12.25
9.75 x - 27/2 = (39 x)/4 - 27/2 and -12.25 = -49/4:
(39 x)/4 - 27/2 = -49/4
Add 27/2 to both sides:
{y = 1/2 (5 x + 27)
(39 x)/4 = 5/4
Multiply both sides by 4/39:
{y = 1/2 (5 x + 27)
x = 5/39
Substitute x = 5/39 into the first equation:
{y = 539/39
x = 5/39
Collect results in alphabetical order:
Answer: {x = 5/39
, y = 539/39
A = P (1 + r)^n where P = initial amount, r = interest rate , n = number of years and A = amount after n years.
So here we have A = 1393(1 + 0.09) ^ 2 ( 0.09 = 9%)
= $1655.02 (answer)
Answer:
Step-by-step explanation:
Solve for z:
-2(z + 3) = -z - 4(z + 2)
-4(z + 2) = -4z - 8:
-2(z + 3) = -z -4z - 8
Grouping like terms, -z - 4z - 8 = (-z - 4z) - 8:
-2(z + 3) = (-z - 4z) - 8
-z - 4z = -5z:
-2 (z + 3) = -5z - 8
Expand out terms of the left hand side:
-2z - 6 = -5 z - 8
Add 5z to both sides:
(5z - 2z) - 6 = (5z - 5z) - 8
5z - 5z = 0:
(5z - 2z) - 6 = -8
5z - 2z = 3z:
3z - 6 = -8
Add 6 to both sides:
3z + (6 - 6) = 6 - 8
6 - 6 = 0:
3z = 6 - 8
6 - 8 = -2:
3z = -2
Divide both sides of 3z = -2 by 3:
Answer:
i do not know sorry
Step-by-step explanation:
