Answer:
c. 7.527
Step-by-step explanation:
We know that 78 percent of the bar is gold and the total weight is 9.65 ounces. Just multiply the total weight by 78%.
9.65(0.78)=7.527
The first three steps for solving the quadratic equation by completing the square are as follows;
1. 
2. 
3. 
Given
The quadratic equation given as 9x^2 + 54x = 7.
<h3>Quadratic equation;</h3>
The highest power of the degree is 2 is known as a quadratic equation.
To solve using the completing the square method.
The first three steps for solving the quadratic equation by completing the square are given below.
1. Write the equation in a way that the constants are on the right side while the terms with x are on the left.

2. Make sure that the coefficient of the x^2 term is 1.

3. Adding a term to both sides that will complete the square on the left side.
This is done by dividing the coefficient of the x term by 2 and squaring it.
The same amount should be added to the right side to balance the equation.

To know more about quadratic equations click the link given below.
brainly.com/question/25963825
Step-by-step explanation:

P = 2(L + W)
L = 4/3W
P = 2(4/3W + W) <=== part 1 is D
when P = 28
28 = 2(4/3W + W)
28/2 = 4/3W + 3/3W
14 = 7/3W
14 / (7/3) = W
14 * 3/7 = W
42/7 = W
6 = W....width is 6 inches
L = 4/3W
L = 4/3(6)
L = 24/3
L = 8....length is 8 inches
A = L * W
A = 8 * 6
A = 48 in^2 <==== part 2
Answer:
(x + 10)(x + 8)
Step-by-step explanation:
Given
x² + 18x + 80
Consider the factors of the constant term (+ 80) which sum to give the coefficient of the x- term (+ 18)
The factors are + 10 and + 8 , since
10 × 8 = + 80 and 10 + 8 = + 18 , then
x² + 18x + 80 = (x + 10)(x + 8) ← in factored form