Julie buys three notebooks. if each notebook cost 30 cent less,
she would have bought one more. how much did she pay for the three
notebooks?

360 cents or $ 3.6

Step-by-step explanation:

Let x be the original cost ( in cents ) of each note book,

After reducing the price by 30 cents,

New cost of each book = x - 30,

According to the question,

3x = 4(x-30)  ( ∵ total cost = number of books × cost of each book ),

3x = 4x - 120

3x - 4x = -120

-x = -120

x = 120

Hence, the cost of three books = 3 × 120 = 360 cents or $ 3.6

center (1,3) with radius 6

step-by-step explanation:

we must complete the square to find the center and radius of the circle.

first make sure the x and y squared terms have 1 as their coefficients. we also make sure x and y terms together.

we now create space between the x and y terms with parenthesis.

we complete the square by taking the middle terms -2x and the -6y - divide each and square them.

we add the squares to both sides.

simplify.

and write the quadratics in factored form.

the center is (h,k) or (1,3). the radius is the square root of 36 which is 6.