Answer:
Mistake in Line 2
Step-by-step explanation:
Line 1
7(6) ÷ 5 + 42
Line 2
7(6) ÷ 5 + 16
Line 3
42 ÷ 5 + 16
Line 4
42 ÷ 21
Line 5
2
To simplify any expression we use order of operation
Line 1 is 7(6) ÷ 5 + 42
Order of operation is PEMDAS
First we start with parenthesis
so we multiply 7(6) in line 2
7*6- 42
So Line 2 is 42 ÷ 5 + 42
Hence there is a mistake in Line 2
4 x 7 = 28 - 30 = -2. His change is 2 dollars.
Answer:
c=4
Step-by-step explanation:
–2c = –c − 4
add c to both sides
-1c=-4
divide both sides by -1
c=4
Step 1:
Calculate the measure of angle ∠ABC



From the triangle in the question,

Step 2:
Calculate the value of AB using the cosine rule below

By substituting the values, we will have
![\begin{gathered} b^2=a^2+c^2-2\times a\times c\times\cos B \\ b^2=10^2+15^2-2\times10\times15\times\cos 115^0 \\ b^2=100+225-300\times(-0.4226) \\ b^2=325+126.78 \\ b^2=451.78 \\ \text{Square root both sides} \\ \sqrt[]{b^2}=\sqrt[]{451.78} \\ b=21.26\operatorname{km} \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20b%5E2%3Da%5E2%2Bc%5E2-2%5Ctimes%20a%5Ctimes%20c%5Ctimes%5Ccos%20B%20%5C%5C%20b%5E2%3D10%5E2%2B15%5E2-2%5Ctimes10%5Ctimes15%5Ctimes%5Ccos%20115%5E0%20%5C%5C%20b%5E2%3D100%2B225-300%5Ctimes%28-0.4226%29%20%5C%5C%20b%5E2%3D325%2B126.78%20%5C%5C%20b%5E2%3D451.78%20%5C%5C%20%5Ctext%7BSquare%20root%20both%20sides%7D%20%5C%5C%20%5Csqrt%5B%5D%7Bb%5E2%7D%3D%5Csqrt%5B%5D%7B451.78%7D%20%5C%5C%20b%3D21.26%5Coperatorname%7Bkm%7D%20%5Cend%7Bgathered%7D)
Hence,
The distance of point A to point C is = 21.26km