Answer:
5 bags of cement are required.
Step-by-step explanation:
Since to make concrete, the ratio of cement to sand is 1: 3, if cement and sand are sold in bags of equal mass, to determine how many bags of cement are required to make concrete using 15 bags of sand the following calculation must be done:
Cement = 1
Sand = 3
3 = 15
1 = X
15/3 = X
5 = X
Therefore, 5 bags of cement are required.
Answer:
(-2 , 5)
(-1 , 0)
(1 , -4)
(3 , 0)
(4 , -5)
Step-by-step explanation:
<u>First solve the equation:</u>
x² - 2x - 3
<em><u>Find two numbers with have a sum of -2 and a product of -3.</u></em>
-3 and 1
(x - 3)(x + 1)
Solve for x:
x - 3 = 0
x = 3
x + 1 = 0
x = -1
You know that the graph will cross the x-axis at -1 and 3.
(-1 , 0)
(3 , 0)
You know that the graph is positive.
<u>Complete the square to find the vertex</u>
x² - 2x - 3
(x - 1)² = x² - 2 + 1
x² - 2x - 3 = x² - 2 + 1 - 2 = (x - 1)² - 2
1 = 0
x = 1
Substitute into the original equation:
x² - 2x - 3 =
1² - (2 * 1) - 3 =
1 - 2 - 3 =
-4
(1 , -4)
<em><u>You can input any two numbers within -10 and 10. Such as -2 and 4.</u></em>
x² - 2x - 3 =
-2² - (2 * -2) - 3 =
4- -4- 3 =
5
(-2 , 5)
x² - 2x - 3 =
4² - (2 * 4) - 3 =
16 - 8 - 3 =
-5
(4 , -5)
Answer:
<h2>560</h2>
Step-by-step explanation:
You must use a combination:

We have <em>n = 16</em>, <em>k = 3</em>.
Substitute:
