<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
5 degrees above is 5°F
3 degrees below is -3°F
6 degrees above is 6°F
2 3/4 below is -2.74°F
Step-by-step explanation:
as we have a point and the slope, we can start with the point-slope form and then transform.
the point-slope form is
y - y1 = a(x - x1)
(x1, y1) being a point on the line, a being the slope.
the slope-interceot form is
y = ax + b
a being the slope again, b being the y-intercept (the y value for x = 0).
so, we have
y - -5 = 5/2 × (x - -4)
y + 5 = 5/2 × (x + 4) = 5x/2 + 5×4/2 = 5x/2 + 10
y = 5x/2 + 5
or
y = (5/2)x + 5
and this is already the slope-intercept form. all done.
Answer:
24 inches represents 9 miles in the map
Step-by-step explanation:
To solve this problem you take into account that 8 inches represents 3 miles and that x represent the number of inches for 9 miles. That is:
8 ------- 3
x ------- 9
This is simply a rule of three, then you calculate:

Hence, 24 inches represents 9 miles in the map