Answer:
See below
Step-by-step explanation:
d = 78° (Vertical angles)
h = 70° (Vertical angles)
Measure of angles d and h are are not equal. therefore they are not congruent.
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>
7x - xy = -18 x = -4
First, fill the -4 in where the "x's" are.
7<u>(-4)</u> - <u>(-4)</u>y = -18
Then, add the 28 over.
-28 + 4y = -18
<u>+28</u> <u>+28
</u>4y = 10
Then, get the variable by itself, so you would divide the 4 over.
4y = 10
<u>÷4</u> <u>÷4
</u>
<em><u>y = 2.5</u></em>
Answer
C
Step-by-step explanation:
14.95+14.95=29.90
19.95+19.95=39.90
39.90+29.90=69.80
