Answer:
The total amount of lawns to be mowed would be 20 in 35 hours.
Step-by-step explanation:
It takes an hour and 45 minutes to mow one lawn. When you multiply the 7 hours by 5 you get 35 hours. Same thing if you multiply the 4 lawns by 5 you get 20 lawns.
Its algebra. The original equation is

To solve for a variable, we reverse the order of operations, beginning with addition/subtraction, and then multiplication/division. To remove a number from one side, we must do the opposite to the other side. In this case, to get rid of the -121 we must add 121 to the -164. This gives us -43. Then, to get the x by itself, we must multiply the other side by 3. -43*3=129
When we are doing the opposite of an operation to the other side, we are really reversing the operation and, to keep both sides equal, we must do whatever we have done to one side to the other side. So when we have -121, we add 121 as it equals 0, therefore it is gone. Since a equation must be balanced, we have to do what we did to the other side (adding 121).
The equation of a circle with center
and radius
is

In your case,

Plug these values into the generic formula and you'll get your equation.
Answer:
105.46 feet
Step-by-step explanation:
We know all three angles (60, 90, and 30), as well as one side, which is adjacent to the 60 degrees. We want to find the side opposite to the 60 degree angle. To do this, we can use tangent, utilizing both opposite and adjacent.
Using tan, we can say that tan(60) = x/58, with x representing the height of the lighthouse (minus 5, because Santos is 5 feet tall and he is measuring the angle from the top of his head). Multiplying both sides by 58, we can get that 58 *tan(60) = x = 100.46. Add 5 to that to get 105.46 feet as your answer.