B is the correct answer for your question I do believe, I hope that helped you. If not I am sorry, I tried to answer fast for you.
Answer:
120 ways
Step-by-step explanation:
To solve the question above, we use combination formula:
Where ;
nCr = n! / (n-r)! r!
10C7 = 10! / (10 - 7)! 7!
10C7 = 10! / 3! 7!
10C7 = (10 * 9 * 8) / 3 * 2 * 1
10C7 = 720 / 6
= 120 ways
1/2 is 0.5 The answer is 0.5 because 1/2 is like a half and we know that a this fraction is less than 1. So .5+.5=1 THE ANSWER IS 0.5!
System of equations:
We'll need one equation for the amount of pizzas, and another for the total cost of the pizzas. In this case, x will represent small pizzas, and y will represent large pizzas.
3x + 4y = 100
x + y = 30
Solving the system of equations:
First, we need to solve for one variable in one equation.
x + y = 30
x = 30 - y
Then, we'll take our equation that is solved for x and plug it into the other equation from above.
3(30 - y) + 4y = 100
Next, we solve for y.
90 - 3y + 4y = 100
90 + y = 100
y = 10
Finally, we take our value for y and plug it back in to the very first equation and solve for x.
x = 30 - 10
x = 20
Answer:
The student has sold 10 large pizzas and 20 small pizzas.
Hope this helps!! :)
Try graphing using the x-intercept and y-intercept.
-15x - 5y = 45
Put in x = 0 to get -5y = 45, making y = -9. Point (0, -9) is on the line.
Put in y = 0 to get -15x = 45, making x = -3. Point (-3, 0) is on the line.
-2x + 6y = 6
Put in x = 0 to get 6y = 6, making y = 1. Point (0, 1) is on the line.
Put in y = 0 to get -2x = 6, making x = -3. Point (-3, 0) is on the line.
(We've actually stumbled on the solution since (-3, 0) is on both lines!)
Graph the two lines using the points found above.
The solution is x = -3, y = 0.
