Let's say that the value invested in the account with a rate of 8% is "x", then the amount invested in the account with a rate of 12% is:

To calculate the total interest we need to calculate the interest of each individual account and sum them:

The total interest is the sum of the two expressions above:

The value invested in the account with 8% interest is 830, the one invested in the account with 12% interest is 1280.
Start with

Expand both parentheses by multiplying both terms by the number outside:

Sum like terms:

Simplify the "+3" on both sides:

Subtract 2x from both sides:

Divide both sides by 2:

Answer:
D. The ratio of the circumference to the diameter is the same for both sides
Step-by-step explanation:
dilation in a shape is either it becoming bigger or smaller, no matter what factor you dilate the shape by its ratio will still remain the same, such as when you simplify a fraction.
(4)3 is also the same thing as 4x3 which is 12n