**Step-by-step explanation:**

AC=AB+BC-cos. AC=100+66-cos. AC=166-0.906. AC=√165.094. AC=12.8

**Answer:**

10 hours

**Step-by-step explanation:**

We can write a ratio to solve

45 pages 300 pages

---------------- = -------------------

1.5 hours x hours

Using cross products

45x = 1.5(300)

45x =450

Divide by 45

45x/45 = 450/45

x = 10

10 hours

B is the image of d

B is the image of e

C is the image of d

Xy = 940

<span>and </span>

<span>Cost = 5(2x) + 5y + 10y (I chose y to be the side with brick). The cost equation simplifies to: </span>

<span>C = 10x + 15y </span>

<span>Replace y in the cost equation with 940/x: </span>

<span>C = 10x + 15(940/x) </span>

<span>C = 10x + 14100/x <---this is the equation you need to minimize. </span>

<span>C' = 10 - 14100/x^2 </span>

<span>10 - 14100/x^2 = 0 </span>

<span>14100/x^2 = 10 </span>

<span>x^2 = 14100/10 = 1410 </span>

<span>x = sqrt(1410) = 37.55 </span>

<span>y = 25.03 <---this is the length of the brick fence.</span>

**Answer:**

the y is 3 not -3 he did 1/3x not just x. the slope and the y axis are wrong

**Step-by-step explanation:**