<span>a. find the number of units of tacos she must sell to minimise her cost.
</span>to find a minimum we need to find the function derivative and make it equal to zero:
dc/dx = 2x - 40 = 0
2x = 40
x = 20
therefore to minimize the cost, she needs to sell 20 units of tacos
<span>b. find the minimum cost.
</span>that can be done by substituting the previous result, 20 tacos, in the original equation:
<span>C(x) = x^2 - 40x + 610
</span>C(20) = (20)^2 - 40(20) + <span>610
</span>= 400 - 800 + 610
= 210
the minimum cost will be 210 dollars
If you would like to solve the system of equations, you can do this using the following steps:
2x - y = -2
x = 14 + 2y
__________
<span>2x - y = -2
</span>2 * (14 + 2y) - y = -2
28 + 4y - y = -2
28 + 3y = -2
3y = -2 - 28
3y = -30 /3
y = -30/3
y = -10
<span>x = 14 + 2y = 14 + 2 * (-10) = 14 - 20 = -6
</span>
(x, y) = (-6, -10)
The correct result would be <span>(-6, -10).</span>
50*25= 1250
2mins 15seconds= 135 seconds
135*3= 405
1250-405 = 845
Your score is 845
We will guess and check to solve this problem
504/9= 56
504/8= 63
504/7= 72
504/6= 84
.....
we can continue the pattern. However, we know that 50 is the product of 8 and 7, so we can use that number
9*8*7=504