Answer:
Top right.
Step-by-step explanation:
So we want a line with a slope of 3 and passes through (2,5).
To do so, we can use the point-slope form.
The point-slope form is:
m is the slope and x₁ and y₁ is an ordered pair.
Thus, let m be 3, y₁ be 5, and x₁ be 2. Thus:
Our answer is the top right :)
Answer:
£110
Step-by-step explanation:
We know how much time it takes for a boiler and a radiator, and we need to know how much it will cost for 1 boiler and 4 radiators. We have an initial cost of £30, and since hes doing a boiler - which we know takes an hour - we can already add £20 for a start of £50.
Now, there are 4 radiators, that take 45 minutes each. We need to use this equation:
We divide by 60 because there are 60 minutes in an hour, and he charges by hour. So:
Now, to find out how much to charge, we need to figure out how much to add to the £50. Since it's £20 an hour, and it takes 3 hours to do the 4 radiators, we need to multiply:
Now we add our totals for a grand total of...
The vertex form:
Use
Other method:
We have
Substitute: