After earning interest, the balance of an account is $420. The new balance is 7/6 of the original balance. Write an equation that can be used to find the original balance b of the account.

420=_

What was the original balance of the account?

$__

How much interest did the account earn?

$__

Equation: 420 = 7/6b, Original balance: $360, Interest earned: $60.

Step-by-step explanation:

Since 420 is 7/6 of the original balance, and of means mulitply, we can make this into an equation, the equation is 420 = 7/6b. Let's solve the equation for b. Multiply both sides by 6 to get 2520 = 7b. Now, let's divide both sides by 7. This gets us 360 = b. This means the original balance was $360. Now, let's find the interest earned. We know that 420 is 7/6 of 360, so that means the interest earned was 1/6 of the original balance. Let's make sure, first. 360/6 is 60, and 360+60 is 420, so everything checks out.

i'm sure goog can you get that answer

let's cover over the formula of the vertex:

y = a(x – h)^2 + k

in this formula, (h,k) are the vertex, always remember that the positive or negative value of the vertex is based on the sign it has.

for example, if the vertex is -3,-6 then both the x and y value would have the positive sign attached to it and if it were a positive x and y value, then a negative sign would be attached to it.

with that being said, for our problem the x value is a positive one so we are looking for a number with a negative sign next to it, in this case the first and second choice.

however, for the first answer choice it isn't quite part of the formula so we know that the answer choice correctly displays the x value.

to confirm, we can see if the -1 fits correctly with the second answer choice, and as mentioned above a negative number will have a positive sign attached to it. so, for our problem we can see that -1 has been changed to +1, so we can confirm that the second answer choice is correct.

hence, our final answer is y=(x - 1)^2 + 1